Comment 9 for bug 663053

Toobuntu: different kernel versions have different initramfs files. Check if your working and non-working have the same conf/conf.d/cryptroot in them.

I find using UUIDs a bit too hard (or at least I'm not used to deal with them so much), that's why I did my initial fix with /dev/sdaX so that I was absolutely sure what partition was the encrypted one.

Eric: If you did dist-upgrade, do you have any old working kernels/initramfs left on your system?