diff --git a/lib/db/postgres7.php b/lib/db/postgres7.php
index 9a4c423b5d1..d3dfb269579 100644
--- a/lib/db/postgres7.php
+++ b/lib/db/postgres7.php
@@ -18,6 +18,7 @@
 // This file is tailored to PostgreSQL 7
 
 function main_upgrade($oldversion=0) {
+   global $CFG;
 
     if ($oldversion < 2003010101) {
         delete_records("log_display", "module", "user");