Index: openacs-4/packages/acs-lang/www/change-locale.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-lang/www/change-locale.tcl,v
diff -u -r1.5 -r1.5.2.1
--- openacs-4/packages/acs-lang/www/change-locale.tcl	5 Jan 2018 22:59:57 -0000	1.5
+++ openacs-4/packages/acs-lang/www/change-locale.tcl	1 Oct 2019 11:49:25 -0000	1.5.2.1
@@ -3,8 +3,15 @@
 } {
     user_locale
     return_url:localurl
+} -validate {
+    valid_user_locale -requires user_locale {
+        if {![::xo::dc 0or1row user_locale_exists {select 1 from ad_locales where locale = :user_locale}] } {
+            ad_complain "invalid user_locale"
+        }
+    }
 }
 
+
 if { [catch {lang::user::set_locale $user_locale} errmsg] } {
     ns_log Error "acs-lang/www/change-locale crashed calling lang::user::set_locale with user_locale='$user_locale'\n$errmsg"
     ad_return_error [_ acs-lang.Error_changing_locale] [_ acs-lang.User_locale_not_set]