I have a ThinkPad T60p w/ factory bluetooth option, but no bluetooth is found in the device manager with either the XP preload or another drive I imaged with Windows 7.
I have installed all updates, updated to latet BIOS, but still no BT device found, no BT radio under FN+F5, all the usual stuff fails. I have no "I/O port access" menu at all under BIOS security and I believe that this is where I would enable BT (if it is in fact installed and not dead).
There should be a setting in the BIOS - you may have to scroll down - switch from hidden to enabled.
If the BIOS shows it active, and yet still now showing in device manager or under FN+F5, then
check that the BT-device module it is still connected to the cable in the LCD assembly. If the LCD were previously serviced, it may have become detacted.
The following hardware guides can help you locate this depending on whether you have the normal (4:3) or widescreen 16:10 versions.