Index: wp-admin/includes/misc.php
===================================================================
--- wp-admin/includes/misc.php	(revision 12815)
+++ wp-admin/includes/misc.php	(working copy)
@@ -245,15 +245,13 @@
 		$var = $vars[$i];
 		global $$var;
 
-		if (!isset( $$var ) ) {
-			if ( empty( $_POST[$var] ) ) {
-				if ( empty( $_GET[$var] ) )
-					$$var = '';
-				else
-					$$var = $_GET[$var];
-			} else {
-				$$var = $_POST[$var];
-			}
+		if ( empty( $_POST[$var] ) ) {
+			if ( empty( $_GET[$var] ) )
+				$$var = '';
+			else
+				$$var = $_GET[$var];
+		} else {
+			$$var = $_POST[$var];
 		}
 	}
 }