I have a Macbook pro....with PGP whole disk encryption...and Snow Leopard......and ran the latest OSX 10.6.5 update. During the reboot....the mac would just hang at the gray screen indefinitely. I rebooted using the "cmd + S" key sequence....and saw that the error where it was hanging stated "Still waiting for root device". Attempting to repair the hard drive using Disk utility off of the install CD failed, as well as attempts to rebuild the drive using Disk Warrior 4.2. I even went to a local Apple Store....and the techs there didn't have a solution other than doing a re-install of OSX. At this point I was ready to cut my losses and erase the drive and do a fresh install. I'M GLAD I DIDN'T. I don't know why I didn't do this first......but I went to PGP's website to download their recovery CD to try it.....and found an article that stated there was a known issue with PGP WDE and the latest 10.6.5 update. I followed the recovery procedures laid out here: https://pgp.custhelp.com/app/answers/detail/a_id/2288/session/L3NpZC9qUGtOMzJmaw==/sno/0 and was able to boot up just fine. I hope this helps others out who are having a similar issue.