You are correct that article #5962 does not consider the Internet upgrade to Lion, but we also don't know if the Snow Leopard Bluetooth driver is current or updated. That said, I was able to get the Apple Bluetooth driver installed using the information in article #113274. HOWEVER, article #113274 is poorly written, and needs some interpretation. It does show how to download the Lion device driver, so starting the process from the Snow Leopard installation DVD is not a problem. Unfortunately, all of the Lion drivers come down as a package, not just the one Apple Bluetooth driver you want, and the package is a huge download. Once downloaded, you need to install WinRAR on the Windows system. That allows you to decompress the Bluetoothinstall.exe file, and get at it's imbedded .inf. Now, you can install the Apple built-in driver manually using windows update driver function. There's a section of #113274 about editing the .ini file for the driver which I never did figure out. I just ignored it, and it seemed to work, but I have no idea what they were trying to accomplish with that portion of instructions. That's the good news. The bad news is, once installed, the Apple Built-in Bluetooth Driver does not seem to fix the problem of losing connectivity to the bluetooth device. I'm trying to get a GPS device to work consistently. I can start it, but over a period of inactivity, I goes away. I have both Windows (Vista in my case) and Lion set to not sleep. I do drop into a screen saver. Sometimes I do not lose the bluetooth connection, but often I do. Sometimes it comes back if I shutdown Vista and pPD, of off and have coffee, restart Parallels and reboot Vista. Sometimes, tho, I have to re-boot Lion to get it back.
I have opened a support incident with PD.