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 -r1.34 -r1.34.4.1
--- openacs-4/packages/acs-subsite/lib/login.tcl	10 Feb 2011 15:17:01 -0000	1.34
+++ openacs-4/packages/acs-subsite/lib/login.tcl	1 Oct 2013 10:03:54 -0000	1.34.4.1
@@ -19,7 +19,7 @@
 			          -parameter AllowSelfRegister \
 			          -default 1]   
 
-if { ![exists_and_not_null package_id] } {
+if { ![info exists subsite_id] || $subsite_id eq "" } {
     set subsite_id [subsite::get_element -element object_id]
 }
 
@@ -68,7 +68,7 @@
 set subsite_url [subsite::get_element -element url]
 set system_name [ad_system_name]
 
-if { [exists_and_not_null return_url] } {
+if { [info exists return_url] && $return_url ne "" } {
     if { [util::external_url_p $return_url] } {
       ad_returnredirect -message "only urls without a host name are permitted" "."
       ad_script_abort
@@ -79,7 +79,7 @@
 
 set authority_options [auth::authority::get_authority_options]
 
-if { ![exists_and_not_null authority_id] } {
+if { ![info exists authority_id] || $authority_id eq "" } {
     set authority_id [lindex [lindex $authority_options 0] 1]
 }
 
@@ -183,12 +183,12 @@
         ad_script_abort
     }
 
-    if { ![exists_and_not_null authority_id] } {
+    if { ![info exists authority_id] || $authority_id eq "" } {
         # Will be defaulted to local authority
         set authority_id {}
     }
 
-    if { ![exists_and_not_null persistent_p] } {
+    if { ![info exists persistent_p] || $persistent_p eq "" } {
         set persistent_p "f"
     }
     if {![element exists login email]} {
@@ -222,7 +222,7 @@
         }
     }
 
-    if { [exists_and_not_null auth_info(account_url)] } {
+    if { [info exists auth_info(account_url)] && $auth_info(account_url) ne "" } {
         ad_returnredirect $auth_info(account_url)
         ad_script_abort
     }
@@ -283,7 +283,7 @@
     # We're logged in
 
     # Handle account_message
-    if { [exists_and_not_null auth_info(account_message)] } {
+    if { [info exists auth_info(account_message)] && $auth_info(account_message) ne "" } {
         ad_returnredirect [export_vars -base "[subsite::get_element -element url]register/account-message" { { message $auth_info(account_message) } return_url }]
         ad_script_abort
     } else {