Index: openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl,v
diff -u -N -r1.189.2.79 -r1.189.2.80
--- openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl	22 Feb 2021 15:19:39 -0000	1.189.2.79
+++ openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl	28 Feb 2021 16:44:18 -0000	1.189.2.80
@@ -3611,6 +3611,9 @@
         # more valid url pairs with host_node_map
 
         foreach location $locations_list {
+            if {$location eq ""} {
+                continue
+            }
             set len [string length $location]
             #ns_log notice "util::external_url_p location match <$location/*> with <$url> sub <[string range $url 0 $len-1]>"
             if {[string range $url 0 $len-1] eq $location} {