Today I started a little playing on the Longhorn Inspirat Theme and the SlateNG-Theme. I wanted it that it seems like Metacity and the menubar are not separated (my screenshot will tell you this better than I am able to do - Sorry for the bad English). I replaced the picture for the titlebar in the Metacity-Theme and the picture for the menubar with exactly the same PNG. But Metacity and the menubar seem to scale differently. There is exactly one length of the window where everything is correct. If I make it smaller or bigger nothing is like I meant it to be.

Any suggestions to solve this problem? Any help would be appreciated.