http://social.msdn.microsoft.com/forums/en-US/sqltools/thread/07db294a-79e5-4a5a-916c-6a51e44a5aa4/
MsiZap.exe is also available inside the Installer Cleanup Utility package (349KB):http://support.microsoft.com/default.aspx?scid=kb;en-us;290301After installation browse to C:\Program Files\Windows Installer Clean Up\ to find MsiZap.exeThis page may be helpful as well:http://blogs.msdn.com/heaths/archive/2007/01/31/how-to-safely-delete-orphaned-patches.aspx