Index: openacs-4/packages/acs-subsite/lib/login.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-subsite/lib/login.tcl,v
diff -u -r1.26 -r1.27
--- openacs-4/packages/acs-subsite/lib/login.tcl	16 Jun 2006 13:56:34 -0000	1.26
+++ openacs-4/packages/acs-subsite/lib/login.tcl	5 Dec 2006 18:56:34 -0000	1.27
@@ -68,7 +68,12 @@
 set subsite_url [subsite::get_element -element url]
 set system_name [ad_system_name]
 
-if { ![exists_and_not_null return_url] } {
+if { [exists_and_not_null return_url] } {
+    if {[util_complete_url_p $return_url]} {
+      ad_returnredirect -message "only urls without a host name are permitted" "."
+      ad_script_abort
+    }
+} else {
     set return_url [ad_pvt_home]
 }