Index: System.Data.SQLite/SQLiteConnection.cs
==================================================================
--- System.Data.SQLite/SQLiteConnection.cs
+++ System.Data.SQLite/SQLiteConnection.cs
@@ -1412,27 +1412,35 @@
     /// </summary>
     /// <param name="functionAttribute">
     /// The <see cref="SQLiteFunctionAttribute" /> object instance containing
     /// the metadata for the function to be bound.
     /// </param>
-    /// <param name="callback">
-    /// The <see cref="Delegate" /> object instance that implements the
-    /// function to be bound.
+    /// <param name="callback1">
+    /// A <see cref="Delegate" /> object instance that helps implement the
+    /// function to be bound.  For aggregate functions, this corresponds to the
+    /// <see cref="SQLiteStepDelegate" /> callback.
+    /// </param>
+    /// <param name="callback2">
+    /// A <see cref="Delegate" /> object instance that helps implement the
+    /// function to be bound.  For aggregate functions, this corresponds to the
+    /// <see cref="SQLiteFinalDelegate" /> callback.  For other callback types,
+    /// it is not used and must be null.
     /// </param>
     public void BindFunction(
         SQLiteFunctionAttribute functionAttribute,
-        Delegate callback
+        Delegate callback1,
+        Delegate callback2
         )
     {
         CheckDisposed();
 
         if (_sql == null)
             throw new InvalidOperationException(
                 "Database connection not valid for binding functions.");
 
         _sql.BindFunction(functionAttribute,
-            new SQLiteDelegateFunction(callback), _flags);
+            new SQLiteDelegateFunction(callback1, callback2), _flags);
     }
 
     ///////////////////////////////////////////////////////////////////////////////////////////////
 
     /// <summary>

Index: System.Data.SQLite/SQLiteFunction.cs
==================================================================
--- System.Data.SQLite/SQLiteFunction.cs
+++ System.Data.SQLite/SQLiteFunction.cs
@@ -738,11 +738,11 @@
             if (at == null)
                 continue;
 
             RegisterFunction(
                 at.Name, at.Arguments, at.FuncType, at.InstanceType,
-                at.Callback);
+                at.Callback1, at.Callback2);
         }
     }
 
     /// <summary>
     /// Alternative method of registering a function.  This method
@@ -759,31 +759,38 @@
     /// The type of SQLite function being resitered (e.g. scalar,
     /// aggregate, or collating sequence).
     /// </param>
     /// <param name="instanceType">
     /// The <see cref="Type" /> that actually implements the function.
-    /// This will only be used if the <paramref name="callback" />
-    /// parameter is null.
+    /// This will only be used if the <paramref name="callback1" />
+    /// and <paramref name="callback2" /> parameters are null.
     /// </param>
-    /// <param name="callback">
-    /// The <see cref="Delegate" /> that implements the function.  If
-    /// this is non-null, the <paramref name="instanceType" /> parameter
-    /// will be ignored when the function is invoked.
+    /// <param name="callback1">
+    /// The <see cref="Delegate" /> to be used for all calls into the
+    /// <see cref="SQLiteFunction.Invoke" />,
+    /// <see cref="SQLiteFunction.Step" />,
+    /// and <see cref="SQLiteFunction.Compare" /> virtual methods.
+    /// </param>
+    /// <param name="callback2">
+    /// The <see cref="Delegate" /> to be used for all calls into the
+    /// <see cref="SQLiteFunction.Final" /> virtual method.
     /// </param>
     public static void RegisterFunction(
         string name,
         int argumentCount,
         FunctionType functionType,
         Type instanceType,
-        Delegate callback
+        Delegate callback1,
+        Delegate callback2
         )
     {
         SQLiteFunctionAttribute at = new SQLiteFunctionAttribute(
             name, argumentCount, functionType);
 
         at.InstanceType = instanceType;
-        at.Callback = callback;
+        at.Callback1 = callback1;
+        at.Callback2 = callback2;
 
         _registeredFunctions.Add(at, null);
     }
 
     /// <summary>
@@ -808,14 +815,16 @@
         if (functionAttribute == null)
         {
             function = null;
             return false;
         }
-        else if (functionAttribute.Callback != null)
+        else if ((functionAttribute.Callback1 != null) ||
+                (functionAttribute.Callback2 != null))
         {
             function = new SQLiteDelegateFunction(
-                functionAttribute.Callback);
+                functionAttribute.Callback1,
+                functionAttribute.Callback2);
 
             return true;
         }
         else if (functionAttribute.InstanceType != null)
         {
@@ -1189,14 +1198,16 @@
   /// </summary>
   public class SQLiteDelegateFunction : SQLiteFunction
   {
       #region Private Constants
       /// <summary>
-      /// This error message is used by the overridden virtual methods when the
-      /// callback has not been set.
+      /// This error message is used by the overridden virtual methods when
+      /// a required <see cref="Delegate" /> property (e.g.
+      /// <see cref="Callback1" /> or <see cref="Callback2" />) has not been
+      /// set.
       /// </summary>
-      private const string NoCallbackError = "No callback is set.";
+      private const string NoCallbackError = "No \"{0}\" callback is set.";
 
       /////////////////////////////////////////////////////////////////////////
 
       /// <summary>
       /// This error message is used by the overridden <see cref="Compare" />
@@ -1210,11 +1221,11 @@
       #region Public Constructors
       /// <summary>
       /// Constructs an empty instance of this class.
       /// </summary>
       public SQLiteDelegateFunction()
-          : this(null)
+          : this(null, null)
       {
           // do nothing.
       }
 
       /////////////////////////////////////////////////////////////////////////
@@ -1222,20 +1233,28 @@
       /// <summary>
       /// Constructs an instance of this class using the specified
       /// <see cref="Delegate" /> as the <see cref="SQLiteFunction" />
       /// implementation.
       /// </summary>
-      /// <param name="callback">
+      /// <param name="callback1">
+      /// The <see cref="Delegate" /> to be used for all calls into the
+      /// <see cref="Invoke" />, <see cref="Step" />, and
+      /// <see cref="Compare" /> virtual methods needed by the
+      /// <see cref="SQLiteFunction" /> base class.
+      /// </param>
+      /// <param name="callback2">
       /// The <see cref="Delegate" /> to be used for all calls into the
-      /// virtual methods needed by the <see cref="SQLiteFunction" />
-      /// class.
+      /// <see cref="Final" /> virtual methods needed by the
+      /// <see cref="SQLiteFunction" /> base class.
       /// </param>
       public SQLiteDelegateFunction(
-          Delegate callback
+          Delegate callback1,
+          Delegate callback2
           )
       {
-          this.callback = callback;
+          this.callback1 = callback1;
+          this.callback2 = callback2;
       }
       #endregion
 
       /////////////////////////////////////////////////////////////////////////
 
@@ -1418,20 +1437,35 @@
       #endregion
 
       /////////////////////////////////////////////////////////////////////////
 
       #region Public Properties
-      private Delegate callback;
+      private Delegate callback1;
+      /// <summary>
+      /// The <see cref="Delegate" /> to be used for all calls into the
+      /// <see cref="Invoke" />, <see cref="Step" />, and
+      /// <see cref="Compare" /> virtual methods needed by the
+      /// <see cref="SQLiteFunction" /> base class.
+      /// </summary>
+      public virtual Delegate Callback1
+      {
+          get { return callback1; }
+          set { callback1 = value; }
+      }
+
+      /////////////////////////////////////////////////////////////////////////
+
+      private Delegate callback2;
       /// <summary>
       /// The <see cref="Delegate" /> to be used for all calls into the
-      /// virtual methods needed by the <see cref="SQLiteFunction" />
-      /// class.
+      /// <see cref="Final" /> virtual methods needed by the
+      /// <see cref="SQLiteFunction" /> base class.
       /// </summary>
-      public virtual Delegate Callback
+      public virtual Delegate Callback2
       {
-          get { return callback; }
-          set { callback = value; }
+          get { return callback2; }
+          set { callback2 = value; }
       }
       #endregion
 
       /////////////////////////////////////////////////////////////////////////
 
@@ -1449,23 +1483,26 @@
       /// </returns>
       public override object Invoke(
           object[] args /* in */
           )
       {
-          if (callback == null)
-              throw new InvalidOperationException(NoCallbackError);
+          if (callback1 == null)
+          {
+              throw new InvalidOperationException(String.Format(
+                  NoCallbackError, "Invoke"));
+          }
 
           SQLiteInvokeDelegate invokeDelegate =
-              callback as SQLiteInvokeDelegate;
+              callback1 as SQLiteInvokeDelegate;
 
           if (invokeDelegate != null)
           {
               return invokeDelegate.Invoke("Invoke", args); /* throw */
           }
           else
           {
-              return callback.DynamicInvoke(
+              return callback1.DynamicInvoke(
                   GetInvokeArgs(args, false)); /* throw */
           }
       }
 
       /////////////////////////////////////////////////////////////////////////
@@ -1490,14 +1527,17 @@
           object[] args,         /* in */
           int stepNumber,        /* in */
           ref object contextData /* in, out */
           )
       {
-          if (callback == null)
-              throw new InvalidOperationException(NoCallbackError);
+          if (callback1 == null)
+          {
+              throw new InvalidOperationException(String.Format(
+                  NoCallbackError, "Step"));
+          }
 
-          SQLiteStepDelegate stepDelegate = callback as SQLiteStepDelegate;
+          SQLiteStepDelegate stepDelegate = callback1 as SQLiteStepDelegate;
 
           if (stepDelegate != null)
           {
               stepDelegate.Invoke(
                   "Step", args, stepNumber, ref contextData); /* throw */
@@ -1506,11 +1546,11 @@
           {
               object[] newArgs = GetStepArgs(
                   args, stepNumber, contextData, false);
 
               /* IGNORED */
-              callback.DynamicInvoke(newArgs); /* throw */
+              callback1.DynamicInvoke(newArgs); /* throw */
 
               UpdateStepArgs(newArgs, ref contextData, false);
           }
       }
 
@@ -1530,23 +1570,26 @@
       /// </returns>
       public override object Final(
           object contextData /* in */
           )
       {
-          if (callback == null)
-              throw new InvalidOperationException(NoCallbackError);
+          if (callback2 == null)
+          {
+              throw new InvalidOperationException(String.Format(
+                  NoCallbackError, "Final"));
+          }
 
-          SQLiteFinalDelegate finalDelegate = callback as SQLiteFinalDelegate;
+          SQLiteFinalDelegate finalDelegate = callback2 as SQLiteFinalDelegate;
 
           if (finalDelegate != null)
           {
-              return finalDelegate.Invoke("Final", contextData);
+              return finalDelegate.Invoke("Final", contextData); /* throw */
           }
           else
           {
-              return callback.DynamicInvoke(GetFinalArgs(
-                  contextData, callback is SQLiteFinalDelegate)); /* throw */
+              return callback1.DynamicInvoke(GetFinalArgs(
+                  contextData, false)); /* throw */
           }
       }
 
       /////////////////////////////////////////////////////////////////////////
 
@@ -1571,23 +1614,27 @@
       public override int Compare(
           string param1, /* in */
           string param2  /* in */
           )
       {
-          if (callback == null)
-              throw new InvalidOperationException(NoCallbackError);
+          if (callback1 == null)
+          {
+              throw new InvalidOperationException(String.Format(
+                  NoCallbackError, "Compare"));
+          }
 
           SQLiteCompareDelegate compareDelegate =
-              callback as SQLiteCompareDelegate;
+              callback1 as SQLiteCompareDelegate;
 
           if (compareDelegate != null)
           {
-              return compareDelegate.Invoke("Compare", param1, param2);
+              return compareDelegate.Invoke(
+                  "Compare", param1, param2); /* throw */
           }
           else
           {
-              object result = callback.DynamicInvoke(GetCompareArgs(
+              object result = callback1.DynamicInvoke(GetCompareArgs(
                   param1, param2, false)); /* throw */
 
               if (result is int)
                   return (int)result;
 

Index: System.Data.SQLite/SQLiteFunctionAttribute.cs
==================================================================
--- System.Data.SQLite/SQLiteFunctionAttribute.cs
+++ System.Data.SQLite/SQLiteFunctionAttribute.cs
@@ -18,11 +18,12 @@
   {
     private string       _name;
     private int          _argumentCount;
     private FunctionType _functionType;
     private Type         _instanceType;
-    private Delegate     _callback;
+    private Delegate     _callback1;
+    private Delegate     _callback2;
 
     /// <summary>
     /// Default constructor, initializes the internal variables for the function.
     /// </summary>
     public SQLiteFunctionAttribute()
@@ -52,11 +53,12 @@
     {
         _name = name;
         _argumentCount = argumentCount;
         _functionType = functionType;
         _instanceType = null;
-        _callback = null;
+        _callback1 = null;
+        _callback2 = null;
     }
 
     /// <summary>
     /// The function's name as it will be used in SQLite command text.
     /// </summary>
@@ -85,12 +87,12 @@
     }
 
     /// <summary>
     /// The <see cref="System.Type" /> object instance that describes the class
     /// containing the implementation for the associated function.  The value of
-    /// this property will not be used if the <see cref="Callback" /> property
-    /// value is set to non-null.
+    /// this property will not be used if either the <see cref="Callback1" /> or
+    /// <see cref="Callback2" /> property values are set to non-null.
     /// </summary>
     internal Type InstanceType
     {
         get { return _instanceType; }
         set { _instanceType = value; }
@@ -99,12 +101,23 @@
     /// <summary>
     /// The <see cref="Delegate" /> that refers to the implementation for the
     /// associated function.  If this property value is set to non-null, it will
     /// be used instead of the <see cref="InstanceType" /> property value.
     /// </summary>
-    internal Delegate Callback
+    internal Delegate Callback1
     {
-        get { return _callback; }
-        set { _callback = value; }
-    }
+        get { return _callback1; }
+        set { _callback1 = value; }
+    }
+
+    /// <summary>
+    /// The <see cref="Delegate" /> that refers to the implementation for the
+    /// associated function.  If this property value is set to non-null, it will
+    /// be used instead of the <see cref="InstanceType" /> property value.
+    /// </summary>
+    internal Delegate Callback2
+    {
+        get { return _callback2; }
+        set { _callback2 = value; }
+    }
   }
 }

Index: Tests/basic.eagle
==================================================================
--- Tests/basic.eagle
+++ Tests/basic.eagle
@@ -3600,64 +3600,134 @@
       lappend result [appendArgs 'myFuncArg [expr {$index + 1}] ']
     }
 
     return $result
   }
+
+  proc getHashCode { value } {
+    if {[isObjectHandle $value]} then {
+      if {$value eq "null"} then {
+        return 0
+      } else {
+        return [object invoke $value GetHashCode]
+      }
+    } else {
+      if {[string length $value] == 0} then {
+        return 0
+      } else {
+        set string [object create String $value]
+
+        return [object invoke $string GetHashCode]
+      }
+    }
+  }
+
+  proc hashManagedArray { array } {
+    set data ""
+
+    if {[isObjectHandle $array] && $array ne "null"} then {
+      if {[object invoke $array GetType.IsArray]} then {
+        for {set index 0} {$index < [$array Length]} {incr index} {
+          set element [$array -create -alias GetValue $index]
+
+          if {[string length $element] > 0} then {
+            append data [$element ToString]
+          } else {
+            append data null
+          }
+        }
+      }
+    }
+
+    return [getHashCode [hash normal sha1 $data]]
+  }
 
   proc myFuncCallback { args } {
     if {[llength $args] == 0} then {
       error "no function arguments"
     }
 
     set name [lindex $args 0]
+
+    if {[isObjectHandle $name] && $name ne "null"} then {
+      set name [object invoke $name ToString]
+    }
 
     switch -exact -- $name {
       Invoke {
-        return $args
+        return [hashManagedArray [lindex $args end]]
       }
       Step {
-        set ctx [lindex $args 1]
+        set varName [lindex $args end]
 
-        if {[string length $ctx] == 0} then {
-          error "invalid aggregate context"
+        if {[string length $varName] == 0} then {
+          error "invalid aggregate context variable name"
+        }
+
+        upvar 1 $varName ctx
+
+        if {![info exists ctx] || [string length $ctx] == 0} then {
+          set ctx [pid]
         }
 
-        global aggregateData
+        set hashCtx [getHashCode $ctx]
+        set hashArgs [hashManagedArray [lindex $args end-2]]
 
-        if {[info exists aggregateData($ctx)]} then {
-          incr aggregateData($ctx)
+        if {[info exists ::aggregateData($hashCtx)]} then {
+          incr ::aggregateData($hashCtx) $hashArgs
         } else {
-          set aggregateData($ctx) 1
+          set ::aggregateData($hashCtx) $hashArgs
         }
       }
       Final {
-        set ctx [lindex $args 1]
+        set ctx [lindex $args end]
 
         if {[string length $ctx] == 0} then {
           error "invalid aggregate context"
         }
 
-        global aggregateData
+        set hashCtx [getHashCode $ctx]
 
-        if {[info exists aggregateData($ctx)]} then {
-          return $aggregateData($ctx)
+        if {[info exists ::aggregateData($hashCtx)]} then {
+          return $::aggregateData($hashCtx)
         } else {
           error "missing aggregate context data"
         }
       }
       Compare {
-        return [string compare -nocase [lindex $args 1] [lindex $args 2]]
+        lappend ::compareResults [object invoke -create \
+            Int32 Parse [string compare -nocase [lindex \
+            $args 1] [lindex $args 2]]]
+
+        return [lindex $::compareResults end]
       }
       default {
         error [appendArgs "unknown function callback \"" $name \"]
       }
     }
   }
+
+  proc myFuncInvokeCallback { param0 objs } {
+    return [myFuncCallback $param0 $objs]
+  }
+
+  proc myFuncStepCallback { param0 objs stepNumber contextDataVarName } {
+    upvar 1 $contextDataVarName $contextDataVarName
+    return [myFuncCallback $param0 $objs $stepNumber $contextDataVarName]
+  }
+
+  proc myFuncFinalCallback { param0 contextData } {
+    return [myFuncCallback $param0 $contextData ]
+  }
+
+  proc myFuncCompareCallback { param0 param1 param2 } {
+    return [myFuncCallback $param0 $param1 $param2]
+  }
 
   setupDb [set fileName data-1.74.db]
 } -body {
-  sql execute $db "CREATE TABLE t1(x INTEGER);"
+  sql execute $db "CREATE TABLE t1(x);"
   sql execute $db "INSERT INTO t1 (x) VALUES(1);"
   sql execute $db "INSERT INTO t1 (x) VALUES(2);"
   sql execute $db "INSERT INTO t1 (x) VALUES(3);"
   sql execute $db "INSERT INTO t1 (x) VALUES('A');"
   sql execute $db "INSERT INTO t1 (x) VALUES('a');"
@@ -3671,23 +3741,40 @@
   for {set argumentCount 0} {$argumentCount < 3} {incr argumentCount} {
     set attribute(1,$argumentCount) [object create \
         System.Data.SQLite.SQLiteFunctionAttribute [appendArgs \
         myFunc1_74_1_ $argumentCount] $argumentCount Scalar]
 
-    $connection BindFunction $attribute(1,$argumentCount) myFuncCallback
+    $connection -marshalflags \
+        {-StrictMatchType +DynamicCallback ForceParameterType} \
+        -parametertypes [list System.Data.SQLite.SQLiteFunctionAttribute \
+            System.Data.SQLite.SQLiteInvokeDelegate Delegate] \
+        BindFunction $attribute(1,$argumentCount) \
+        myFuncInvokeCallback null
 
     set attribute(2,$argumentCount) [object create \
         System.Data.SQLite.SQLiteFunctionAttribute [appendArgs \
         myFunc1_74_2_ $argumentCount] $argumentCount Aggregate]
 
-    $connection BindFunction $attribute(2,$argumentCount) myFuncCallback
+    $connection -marshalflags \
+        {-StrictMatchType +DynamicCallback ForceParameterType} \
+        -parametertypes [list System.Data.SQLite.SQLiteFunctionAttribute \
+            System.Data.SQLite.SQLiteStepDelegate \
+            System.Data.SQLite.SQLiteFinalDelegate] \
+        BindFunction $attribute(2,$argumentCount) \
+        myFuncStepCallback myFuncFinalCallback
   }
 
   set attribute(3,0) [object create \
-      System.Data.SQLite.SQLiteFunctionAttribute myFunc1_74_3 0 Collation]
+      System.Data.SQLite.SQLiteFunctionAttribute myFunc1_74_3 0 \
+      Collation]
 
-  $connection BindFunction $attribute(3,0) myFuncCallback
+  $connection -marshalflags \
+      {-StrictMatchType +DynamicCallback ForceParameterType} \
+      -parametertypes [list System.Data.SQLite.SQLiteFunctionAttribute \
+          System.Data.SQLite.SQLiteCompareDelegate Delegate] \
+      BindFunction $attribute(3,0) \
+      myFuncCompareCallback null
 
   for {set argumentCount 0} {$argumentCount < 3} {incr argumentCount} {
     lappend result [catch {
       sql execute $db [appendArgs \
           "SELECT " myFunc1_74_1_ $argumentCount ( \
@@ -3700,11 +3787,12 @@
           [join [getMyFuncArgs $argumentCount] ,] )\;]
     } error] $error
   }
 
   lappend result [catch {
-    sql execute $db "SELECT x FROM t1 ORDER BY x COLLATE myFunc1_74_3;"
+    sql execute -execute reader -format list $db \
+        "SELECT x FROM t1 ORDER BY x COLLATE myFunc1_74_3;"
   } error] $error
 
   lappend result [$connection UnbindAllFunctions false]
 
   for {set argumentCount 0} {$argumentCount < 3} {incr argumentCount} {
@@ -3722,29 +3810,50 @@
     } error] [expr {[string first [appendArgs \
         "no such function: myFunc1_74_2_" $argumentCount] $error] != -1}]
   }
 
   lappend result [catch {
-    sql execute $db "SELECT x FROM t1 ORDER BY x COLLATE myFunc1_74_3;"
+    sql execute -execute reader -format list $db \
+        "SELECT x FROM t1 ORDER BY x COLLATE myFunc1_74_3;"
   } error] [expr {[string first "no such collation sequence: myFunc1_74_3" \
       $error] != -1}]
 
+  lappend result [array size aggregateData]
+  lappend result [testArrayGet aggregateData]
+
   set result
 } -cleanup {
   cleanupDb $fileName
 
   freeDbConnection
 
-  catch {object removecallback myFuncCallback}
+  catch {object removecallback myFuncCompareCallback}
+  catch {object removecallback myFuncFinalCallback}
+  catch {object removecallback myFuncStepCallback}
+  catch {object removecallback myFuncInvokeCallback}
+
+  catch {
+    foreach compareResult $compareResults {
+      catch {object dispose $compareResult}
+    }
+  }
 
-  unset -nocomplain result error aggregateData argumentCount attribute \
-      connection db fileName
+  unset -nocomplain result error compareResult compareResults \
+      aggregateData argumentCount attribute connection db fileName
 
+  rename myFuncCompareCallback ""
+  rename myFuncFinalCallback ""
+  rename myFuncStepCallback ""
+  rename myFuncInvokeCallback ""
   rename myFuncCallback ""
+  rename hashManagedArray ""
+  rename getHashCode ""
   rename getMyFuncArgs ""
 } -constraints {eagle command.object monoBug28 command.sql compile.DATA SQLite\
-System.Data.SQLite} -result {}}
+System.Data.SQLite} -match regexp -result {^0 -1 0 -1 0 -1 0 -1 0 -1 0 -1 0 \{1\
+2 3 A a M m Z z\} True 1 True 1 True 1 True 1 True 1 True 1 True 1 True 1\
+\{(?:-)?\d+ (?:-)?\d+\}$}}
 
 ###############################################################################
 
 reportSQLiteResources $test_channel