Ecnrypted Windows Vista Backup? (not EFS)

Hi
I am trying to use Windows Vista backup but I want to save my backups
encrypted. That is a normal function provided by most backup tools nowadays,
but Windows Vista seems to lack that.
Now, I tried to solve this problem by using TrueCrypt to create a logical
on-the-fly encrypted drive and try to save my backup there. When I try to
setup a backup, the logical drive, is not listed as one of the possible
backup destination.
Is there anyway to use the backup tool and encrypt the backup files or
should I should skip using windows vista backup tool?

you could just encrypt the drive with vista that you want to make the backup image on.
gives the same result that your after