Index: wp-admin/admin-ajax.php
===================================================================
--- wp-admin/admin-ajax.php	(revision 13532)
+++ wp-admin/admin-ajax.php	(working copy)
@@ -1023,7 +1023,7 @@
 
 	if ( is_array($hidden) ) {
 		$hidden = array_diff( $hidden, array('submitdiv', 'linksubmitdiv') ); // postboxes that are always shown
-		update_user_meta($user->ID, 'meta-box-hidden_'.$page, $hidden);
+		update_user_meta($user->ID, $wpdb->prefix.'meta-box-hidden_'.$page, $hidden);
 	}
 
 	die('1');
@@ -1041,7 +1041,7 @@
 		die('-1');
 
 	if ( is_array($hidden) )
-		update_user_meta($user->ID, "manage-$page-columns-hidden", $hidden);
+		update_user_meta($user->ID, $wpdb->prefix."manage-$page-columns-hidden", $hidden);
 
 	die('1');
 	break;
@@ -1058,10 +1058,10 @@
 		die('-1');
 
 	if ( $order )
-		update_user_option($user->ID, "meta-box-order_$page", $order);
+		update_user_option($user->ID, $wpdb->prefix."meta-box-order_$page", $order);
 
 	if ( $page_columns )
-		update_user_meta($user->ID, "screen_layout_$page", $page_columns);
+		update_user_meta($user->ID, $wpdb->prefix."screen_layout_$page", $page_columns);
 
 	die('1');
 	break;