Most likely SP2 overwrote the uxtheme.dll file with the newer SP2 version of the same file
You should use Neowin's UXTheme patcher:
http://www.neowin.net/forum/index.php?showtopic=140707
You should use Neowin's UXTheme patcher:
http://www.neowin.net/forum/index.php?showtopic=140707