Normally, all controls in login screen (button, textbox, etc..) have the current gtk-theme style. But after Compiz crashed (always happen when I enable or disable a plugin), the style has gone (no more transparent button, rounder textbox, or my current icon theme), instead there are ugly windows-95-like buttons, textbox and unknown-theme icon.
Is this a compiz bug? How could I fix it?
Thanks for your time! PS: Im on Ubuntu 12.04 (Unity).
This is my Ubuntu login screen:


This is default ubuntu login screen:


Im on Dell Vostro 1540 with Intel HD 3000 VGA. At first, my login screen looks nothing wrong. But after compiz crashed (when I enable or disable any plugin), the login screen looks like the above pictures. So, I dont think my graphics card is the problem.
