Index: openacs-4/packages/acs-subsite/www/group-leave.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-subsite/www/group-leave.tcl,v
diff -u -r1.2 -r1.2.20.1
--- openacs-4/packages/acs-subsite/www/group-leave.tcl	30 Jan 2004 15:17:31 -0000	1.2
+++ openacs-4/packages/acs-subsite/www/group-leave.tcl	27 Aug 2013 12:20:37 -0000	1.2.20.1
@@ -30,7 +30,7 @@
 
 }
 
-if { ![exists_and_not_null return_url] } {
+if { (![info exists return_url] || $return_url eq "") } {
     set return_url "../"
 }