Problems with Cryptoloop on FC 4

[Mailinglist]

Hello list,

I try to set up a crypted partition on my FC4.
But I failed with following answer:

losetup -e -aes-256 /dev/loop0 /root/test
Password: [test]
ioctl: LOOP_SET_STATUS: Invalid argument

Im using the kernel  2.6.14-1.1637_FC4 and the modules are loaded:

#lsmod
Module                  Size  Used by
aes                    27777  0
cryptoloop              3649  0
loop                   16713  1 cryptoloop

What do I wrong?

Thanks for help!