I'm running Postbox 3 in Wine (pretty sure it's Wine 1.4~rc5-0ubuntu1~ppa1~oneiric1 from the Wine Team PPA). Also using Unity with Compiz in Oneiric.

Tooltips and drop-down menus have shadows, and when the tooltips or menus disappear, often there are relics of these shadows left on the screen, either black rectangles or translucent gray ones.

Because Postbox is built on Thunderbird, is this a problem with XUL maybe? I haven't installed Firefox or Thunderbird to test.

Is there a way to disable shadows for these elements in Wine? Or is there some DLL or something I can install to solve this?