diff --git a/ChangeLog b/ChangeLog
index 0d2f19599..074ac383c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2008-08-27  Mike Kestner  <mkestner@novell.com>
+
+	* generator/ManagedCallString.cs: fixes for data parameter hiding
+	in native to managed callback generation.
+
 2008-08-20  Mike Kestner  <mkestner@novell.com>
 
 	* glib/Object.cs:
diff --git a/generator/ManagedCallString.cs b/generator/ManagedCallString.cs
index 646caf444..290ad86e5 100644
--- a/generator/ManagedCallString.cs
+++ b/generator/ManagedCallString.cs
@@ -35,15 +35,17 @@ namespace GtkSharp.Generation {
 
 		public ManagedCallString (Parameters parms, bool drop_first)
 		{
+			bool has_cb = false;
 			for (int i = drop_first ? 1 : 0; i < parms.Count; i ++) {
 				Parameter p = parms [i];
 				if (p.IsLength && i > 0 && parms [i-1].IsString) 
 					continue;
 				else if (p.Scope == "notified") {
+					has_cb = true;
 					user_data_param = parms[i+1].Name;
 					destroy_param = parms[i+2].Name;
 					i += 2;
-				} else if (p.IsUserData && (i == parms.Count - 1) && (parms.HideData || parms [i-1].Generatable is CallbackGen)) {
+				} else if (p.IsUserData && (parms.HideData || has_cb)) {
 					user_data_param = p.Name;
 					continue;
 				} else if (p is ErrorParameter) {
@@ -54,9 +56,10 @@ namespace GtkSharp.Generation {
 
 				if (p.PassAs != String.Empty && (p.Name != p.FromNative (p.Name)))
 					this.special.Add (true);
-				else if (p.Generatable is CallbackGen)
+				else if (p.Generatable is CallbackGen) {
+					has_cb = true;
 					this.special.Add (true);
-				else
+				} else
 					this.special.Add (false);
 			}
 		}