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 -r1.40 -r1.41
--- openacs-4/packages/acs-lang/tcl/locale-procs.tcl	7 Aug 2017 23:47:56 -0000	1.40
+++ openacs-4/packages/acs-lang/tcl/locale-procs.tcl	1 Mar 2018 11:49:24 -0000	1.41
@@ -169,7 +169,7 @@
     ref-timezones and acs-reference packages need to be installed.
     Those packages are currently not part of the OpenACS kernel.
 } {
-    return [apm_package_installed_p ref-timezones]
+    return [expr {[apm_package_id_from_key ref-timezones] != 0}]
 }
     
 ad_proc -public lang::system::set_timezone {