Index: openacs-4/packages/xotcl-core/www/index.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-core/www/index.tcl,v
diff -u -r1.8.2.2 -r1.8.2.3
--- openacs-4/packages/xotcl-core/www/index.tcl	30 Dec 2015 18:09:14 -0000	1.8.2.2
+++ openacs-4/packages/xotcl-core/www/index.tcl	27 May 2016 08:43:44 -0000	1.8.2.3
@@ -4,11 +4,17 @@
   @author Gustaf Neumann
   @cvs-id $Id$
 } -query {
-  {all_classes:optional 0}
+  {all_classes:notnull 0}
 } -properties {
   title:onevalue
   context:onevalue
   output:onevalue
+} -validate {
+  check_enum -requires all_classes {
+    if {$all_classes ni {0 1}} {
+      ad_complain "value not in enumeration domain"
+    }
+  }
 }
 
 set title "XOTcl Classes Defined in Connection Threads"