Index: trunk/Include/Classes/System/Runtime/InteropServices/GCHandle.ab
===================================================================
--- trunk/Include/Classes/System/Runtime/InteropServices/GCHandle.ab	(revision 340)
+++ trunk/Include/Classes/System/Runtime/InteropServices/GCHandle.ab	(revision 388)
@@ -36,4 +36,7 @@
 
 	Static Function FromIntPtr(ip As LONG_PTR) As GCHandle
+		If ip = 0 Then
+			Throw New InvalidOperationException("GCHandle.FromIntPtr: ip is 0.")
+		End If
 		FromIntPtr = New GCHandle
 		FromIntPtr.handle = ip As VoidPtr