diff --git a/ChangeLog b/ChangeLog
index 66c2f035..3f501fda 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2005-02-19 02:29 Gregory John Casamento <greg_casamento@yahoo.com>
+
+	* Defaults.plist: Added new default "AllowUserBundles" to 
+	disable new code which prevents Gorm from running if a 
+	user bundle is present.
+	* Gorm.m: Added code in [Gorm applicationDidFinishLaunching:]
+	to warn the user and quit, unless the above default is set,
+	if there is a user bundle loaded.  It will give the user
+	a few panels explaining what's going on.
+
 2005-02-15 23:37 Gregory John Casamento <greg_casamento@yahoo.com>
 
 	* GormPosingView.[hm]: Removed.
diff --git a/Defaults.plist b/Defaults.plist
index 21037ba1..e9205f2e 100644
--- a/Defaults.plist
+++ b/Defaults.plist
@@ -1,22 +1,25 @@
 {
-  PreloadHeaders = NO;
-  ShowPalettes = YES;
-  ShowInspectors = YES;	
-  HeaderList = ();
-  CellSizeWidth = 72;
-  ArchiveType = Typed;
-  GuideColor = {
-    alpha = 1;
-    blue = 0;
-    green = 0;
-    red = 1;
-  };	
-  BuiltinPalettes = (
-    "0Menus.palette",
-    "1Windows.palette",
-    "2Controls.palette",
-    "3Containers.palette",
-    "4Data.palette"
-  );
-  UserPalettes = ();
-}
+    AllowUserBundles = NO;
+    ArchiveType = Typed;
+    BuiltinPalettes = (
+	0Menus.palette,
+	1Windows.palette,
+	2Controls.palette,
+	3Containers.palette,
+	4Data.palette
+    );
+    CellSizeWidth = 72;
+    GuideColor = {
+	alpha = 1;
+	blue = 0;
+	green = 0;
+	red = 1;
+    };
+    HeaderList = (
+    );
+    PreloadHeaders = NO;
+    ShowInspectors = YES;
+    ShowPalettes = YES;
+    UserPalettes = (
+    );
+}
\ No newline at end of file
diff --git a/Gorm.m b/Gorm.m
index 6cdba583..96455b70 100644
--- a/Gorm.m
+++ b/Gorm.m
@@ -44,6 +44,9 @@ NSString *GormResizeCellNotification = @"GormResizeCellNotification";
 // Define this as "NO" initially.   We only want to turn this on while loading or testing.
 static BOOL _isInInterfaceBuilder = NO;
 
+// Has poseAs: been called?
+static BOOL _illegalClassSubstitution = NO;
+
 static NSImage *gormImage = nil;
 static NSImage *testingImage = nil;
 
@@ -107,8 +110,14 @@ static NSImage *testingImage = nil;
 @implementation NSObject (GormPrivate)
 + (void) poseAsClass: (Class)aClassObject
 {
+  BOOL allow = [[NSUserDefaults standardUserDefaults] boolForKey: @"AllowUserBundles"];
+
   // disable poseAs: while in Gorm.
-  // class_pose_as(self, aClassObject);
+  class_pose_as(self, aClassObject);
+  if(!allow)
+    {
+      _illegalClassSubstitution = YES;
+    }
 }
 @end
 
@@ -331,12 +340,25 @@ static NSImage *testingImage = nil;
     {
       [[[self palettesManager] panel] makeKeyAndOrderFront: self];
     }
-  if((a = [defaults arrayForKey: @"GSAppKitUserBundles"]) != nil)
+  if((a = [defaults arrayForKey: @"GSAppKitUserBundles"]) != nil ||
+     _illegalClassSubstitution == YES)
     {
       if([a count] > 0)
 	{
-	  NSLog(@"WARNING: Gorm has detected that you are using user bundles.  Please make certain that these are compatible with Gorm as some bundles can cause issues which may corrupt your .gorm files.");
+	  NSRunAlertPanel(_(@"User Bundle Warning"), 
+			  _(@"Gorm has detected that you are using user bundles.  Please make certain that these are compatible with Gorm as some bundles can cause issues which may corrupt your .gorm files."),
+			  _(@"OK"), nil, nil);
 	}
+
+      if(_illegalClassSubstitution == YES)
+	{
+	  NSRunAlertPanel(_(@"Illegal Class Substitution"), 
+			  _(@"A bundle has invoked 'poseAsClass:', this could corrupt .gorm files.  Quitting."),
+			  _(@"OK"), nil, nil);
+	  NSBeep();
+	  [self terminate: self];
+	}
+
     }
   if(GSGetMethod([GSNibContainer class],@selector(awakeWithContext:),YES,YES) == NULL)
     {