Index: openacs-4/packages/acs-tcl/acs-tcl.info
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/acs-tcl.info,v
diff -u -N -r1.70.2.13 -r1.70.2.14
--- openacs-4/packages/acs-tcl/acs-tcl.info	15 May 2016 18:22:49 -0000	1.70.2.13
+++ openacs-4/packages/acs-tcl/acs-tcl.info	19 May 2016 08:39:02 -0000	1.70.2.14
@@ -9,7 +9,7 @@
     <implements-subsite-p>f</implements-subsite-p>
     <inherit-templates-p>t</inherit-templates-p>
     
-    <version name="5.9.1d5" url="http://openacs.org/repository/download/apm/acs-tcl-5.9.1d5.apm">
+    <version name="5.9.1d6" url="http://openacs.org/repository/download/apm/acs-tcl-5.9.1d6.apm">
         <owner url="http://openacs.org">OpenACS</owner>
         <summary>The Kernel Tcl API library.</summary>
         <release-date>2016-05-15</release-date>
@@ -18,7 +18,7 @@
         <license>GPL version 2</license>
         <maturity>3</maturity>
 
-        <provides url="acs-tcl" version="5.9.1d5"/>
+        <provides url="acs-tcl" version="5.9.1d6"/>
         <requires url="acs-bootstrap-installer" version="5.9.0"/>
         <requires url="acs-kernel" version="5.9.1d4"/>
 
Index: openacs-4/packages/acs-tcl/catalog/acs-tcl.en_US.ISO-8859-1.xml
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/catalog/acs-tcl.en_US.ISO-8859-1.xml,v
diff -u -N -r1.25 -r1.25.2.1
--- openacs-4/packages/acs-tcl/catalog/acs-tcl.en_US.ISO-8859-1.xml	24 Jun 2015 07:10:29 -0000	1.25
+++ openacs-4/packages/acs-tcl/catalog/acs-tcl.en_US.ISO-8859-1.xml	19 May 2016 08:39:02 -0000	1.25.2.1
@@ -43,6 +43,7 @@
   <msg key="lt_name_does_not_appear__1">%name% does not appear to be a valid US phone number.</msg>
   <msg key="lt_name_does_not_appear__2">%name% does not appear to be a boolean value.</msg>
   <msg key="lt_name_is_not_a_natural">%name% is not a natural number, that is an integer greater than or equal to 0.</msg>
+  <msg key="lt_name_is_not_valid">%name% is not valid</msg>
   <msg key="lt_name_is_not_a_valid_S">%name% is not a valid SQL identifier</msg>
   <msg key="lt_name_is_not_an_intege">%name% is not an integer</msg>
   <msg key="lt_name_is_not_a_word">%name% contains non-word characters</msg>
Index: openacs-4/packages/acs-tcl/tcl/tcl-documentation-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/tcl-documentation-procs.tcl,v
diff -u -N -r1.36.2.21 -r1.36.2.22
--- openacs-4/packages/acs-tcl/tcl/tcl-documentation-procs.tcl	18 May 2016 07:08:05 -0000	1.36.2.21
+++ openacs-4/packages/acs-tcl/tcl/tcl-documentation-procs.tcl	19 May 2016 08:39:02 -0000	1.36.2.22
@@ -407,6 +407,10 @@
     <dd>Pluggable filter, installed by default, that makes sure hat argument contains only Tcl word
     characters (as defined by \w in Tcl regular expressions, i.e. characers, digits and underscore).
 
+    <dt><a href="proc-view?proc=ad_page_contract_filter_proc_return_url"><b>return_url</b></a>
+    <dd>Pluggable filter, installed by default, that makes sure hat argument contains a valid
+    (non-external) return url, which can be used in ad_returnredirect without throwing an error.
+
     </dl>
 
     <a href="/api-doc/proc-search?query_string=ad_page_contract_filter_proc&search_type=Search&name_weight=5&param_weight=3&doc_weight=2">more filters...</a>
@@ -2137,9 +2141,24 @@
     return 0
 }
 
+ad_page_contract_filter return_url { name value } {
+    Checks whether the value is a an acceptable
+    (non-external) return url, which can be used
+    in ad_returnredirect without throwing an error.
 
+    @author Gustaf Neumann
+    @creation-date 19 Mai 2016
+} {
 
+    if { $value eq "" || [util::external_url_p $value]} {
+        ad_complain [_ acs-tcl.lt_name_is_not_valid]
+        return 0
+    }
+    return 1
+}
 
+
+
 ####################
 # 
 # Standard filter rules