I'm writing this on a Debian machine that is using ZFS. It's Red Hat that has a problem with ZFS, not Debian.
Are you using the vanilla Debian kernel? The advantage of Ubuntu is that you don't need to depend on DKMS for something as vital as a file system.
Are you using the vanilla Debian kernel? The advantage of Ubuntu is that you don't need to depend on DKMS for something as vital as a file system.