--- userpoints.install	2010-11-29 17:46:20.000000000 +0100
+++ new-userpoints.install	2010-12-01 15:53:05.164769900 +0100
@@ -174,7 +174,7 @@ function userpoints_install() {
  */
 function userpoints_uninstall() {
   drupal_uninstall_schema('userpoints');
-  db_query("DELETE FROM {variable} WHERE name like '%userpoints%'");
+  db_query("DELETE FROM {variable} WHERE name like 'userpoints_%'");
 
   $vid = db_result(db_query("SELECT vid FROM {vocabulary} WHERE module='userpoints'"));
   if ($vid) {