Hibernate Restarts Rather Than Shutdown

I've got a Dell Latitude D810 running WinXP Pro (Build
2600.xpsp.051011-1528 SP2) and I've run into some hibernation issues
lately. I can shutdown, restart, nd stand-by without any problems.
But when I hibernate, the system restarts immediately rather than
shutting down. I believe this behaviour started when I installed IVT
BlueSoleil bluetooth software. I have since uninstalled said software
and reinstalled it several times. In fact, before uninstalling it for
the first time, Windows would hang at the "Preparing to hibernate..."
screen. At this time, shutdown, restart, and stand-by also worked
fine. I then uninstalled and reinstalled BlueSoleil, and now hibernate
mostly works (it completes the hibernation, but restarts instead of
turning off my laptop). I've got all of the updates available via
Microsoft Update, and I've got the latest BIOS for my laptop. All the
ACPI stuff appears to be installed and working fine. I've also tried
hibernation with BlueSoleil uninstalled completely, and hibernation
continues to restart rather than shutting down.

Any suggestions?

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