Index: openacs-4/packages/acs-lang/tcl/locale-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-lang/tcl/locale-procs.tcl,v
diff -u -r1.39.2.4 -r1.39.2.5
--- openacs-4/packages/acs-lang/tcl/locale-procs.tcl	29 May 2016 11:15:30 -0000	1.39.2.4
+++ openacs-4/packages/acs-lang/tcl/locale-procs.tcl	29 May 2016 11:25:23 -0000	1.39.2.5
@@ -322,7 +322,7 @@
         #
         # Check, if someone hacked the cookie
         #
-        if {![lang::conn::valid_locale_p $locale]} {
+        if {$locale ne "" && ![lang::conn::valid_locale_p $locale]} {
             error "invalid locale cookie '$locale'"
         }
     } else {