Index: generic/tclVar.c
===================================================================
RCS file: /cvsroot/tcl/tcl/generic/tclVar.c,v
retrieving revision 1.69.2.14
diff -u -r1.69.2.14 tclVar.c
--- generic/tclVar.c	10 May 2007 18:23:58 -0000	1.69.2.14
+++ generic/tclVar.c	4 Mar 2009 16:32:40 -0000
@@ -2690,7 +2690,7 @@
 
 	    varValuePtr = TclPtrSetVar(interp, varPtr, arrayPtr, part1, NULL, 
 	            objv[i], (TCL_APPEND_VALUE | TCL_LEAVE_ERR_MSG));
-	    if (varValuePtr == NULL) {
+	    if (varValuePtr == ((Interp *) interp)->emptyObjPtr) {
 		return TCL_ERROR;
 	    }
 	}
