Index: openacs-4/packages/dotlrn/tcl/community-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/dotlrn/tcl/community-procs.tcl,v
diff -u -r1.198.2.1 -r1.198.2.2
--- openacs-4/packages/dotlrn/tcl/community-procs.tcl	21 Jul 2007 14:50:02 -0000	1.198.2.1
+++ openacs-4/packages/dotlrn/tcl/community-procs.tcl	4 Sep 2007 08:15:17 -0000	1.198.2.2
@@ -1034,13 +1034,22 @@
         {-package_id ""}
     } {
         Returns the community id depending on the package_id
-        we're at, or the package_id passed in
+        we're at, or the package_id passed in.
+
+	If no community_id found, return empty_string
+
+	@param package_id PackageID for which to search the community_id for
+	@return community_id of the community where the package is mounted, empty string if not found
     } {
         if {[empty_string_p $package_id]} {
             set package_id [site_node_closest_ancestor_package -default [ad_conn package_id] dotlrn]
         }
 
-        return [util_memoize "dotlrn_community::get_community_id_not_cached -package_id $package_id"]
+	if {$package_id ne ""} {
+	    return [util_memoize "dotlrn_community::get_community_id_not_cached -package_id $package_id"]
+	} else {
+	    return ""
+	}
     }
 
     ad_proc -private get_community_id_not_cached {