If you have yet to upgrade then follow these simple steps to avoid the problem.
1. Take a snapshot, backup or do something to make sure you can always get back if something goes wrong.
2. Start the Lion guest and the open a Terminal under Applications Utilities
3. Copy the existing AppleLSIFusionMPT.kext to the current directory:
cp -rv /System/Library/Extensions/AppleLSIFusionMPT.kext .4. Now run the 10.7.2 update package but stop and do not reboot - if you do go find that backup or snapshot as you will have to start again! See the attached image.
5. Go back to the terminal prompt and run these 2 commands. You will be prompted for your password.
sudo rm -rfv /System/Library/Extensions/AppleLSIFusionMPT.kext sudo cp -rv AppleLSIFusionMPT.kext /System/Library/Extensions6. Now you can reboot.
If everything is done correctly should reboot successfully using the older SCSI driver.