--- class-wp-admin-bar.php	2011-11-27 21:41:24.000000000 -0500
+++ class-wp-admin-bar.2.php	2011-11-28 09:46:22.000000000 -0500
@@ -120,9 +120,11 @@
 	}
 
 	public function remove_node( $id ) {
-		$node = $this->nodes[ $id ];
-		unset( $this->nodes[ $id ] );
-		return get_object_vars( $node );
+		if(!empty($this->nodes[ $id ])){
+			$node = $this->nodes[ $id ];
+			unset( $this->nodes[ $id ] );
+			return get_object_vars( $node );
+		}
 	}
 
 	public function render() {