diff --git a/AppKit/CPToolbar.j b/AppKit/CPToolbar.j
index b4d9069..8eb5ef4 100644
--- a/AppKit/CPToolbar.j
+++ b/AppKit/CPToolbar.j
@@ -264,8 +264,9 @@ var _CPToolbarItemVisibilityPriorityCompare = function(lhs, rhs)
             item = [[_delegate toolbar:self itemForItemIdentifier:identifier willBeInsertedIntoToolbar:YES] copy];
         
         if (item == nil)
-            [CPException raise:CPInvalidArgumentException
-                        format:@"_delegate %@ returned nil toolbar item returned for identifier %@", _delegate, identifier];
+            [CPException 
+              raise:CPInvalidArgumentException
+              reason:@"_delegate %@ returned nil toolbar item returned for identifier %@", _delegate, identifier];
         
         [_items addObject:item];
     }