After my move to md-crypt for my home directory I have also moved my swap partition over to LVM. This has caused a couple of problems with hibernate and recover from disk.
In the end I had to hand hack some files in the initrd to make it load the LVM before it tried to do a resume bit of a fudge. There are a load of bugs about it filed in the Ubuntu database so I did not really have anything to add.
Also to get the crypto stuff to work I had to remove the splash kernel option from the grub setup so that it would prompt me for a password!
As I have hacked things I am sure this will come back to bite me but it's working for now and that will do.