VLUCVB.exe or GIVLS5.exe Any ideas?

One of my customers has a sytem that is infected with two hijack programs that Ad-aware and Spy Sweepers keeps reporting. They are VLUCVB.EXE and GIVLS5.EXE. You can allow the spyware program to delete them, but next time you reboot, they reinstall themselves. Unalbe to find any reference to how to kill them for good. Has any one had any previous experience trying to remove either one of these?