No idea what package you are using, but the kernel has no control over userspace utilities working like this (it's not the kernel that asks for the password).
** Changed in: linux-source-2.6.17 (Ubuntu) Status: Unconfirmed => Rejected -- /etc/init.d/cryptdisks does not accept typed passkeys https://launchpad.net/bugs/72739 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs