I tried to upgrade from 10.10 to 11.04 but it crashed. It couldn't mount disk drives so I did a new installation without erasing the previous drives. Now I can't access access-your-private-data.
I have this same problem, and discovered ecryptfs-recover-private from Dustin Kirkland's blog. This utility interactively asks for your login password, which I have, and then mounted my old home directory in /tmp/ecrypt.hAsHeD and I am now able to copy out everything I need.