How can I backup my system to a remote server (AFP, Samba, or NFS share)?

Question

Here's the goal: I have a backup server with a ZFS filesystem with built in compression and snapshots. All our machines backup there nightly with rsync, and then a ZFS snapshot is taken, so we have backups of how eveach machine looked at the end of every day.

The problem is that with Mac OS X, the resource forks are not copied since the remote machine does not support resource forks. What I would like to do is rsync to a .DMG file which resides on the backup server. This way, I'd have an exact, bootable image of how my system looked each night.

As a bonus, the backup server is also a NetBoot server, so this would actually allow me to boot from how my mac was at any point in history.

I created an image of my Mac's drive and copied it to the backup server. Now, when I open it on my mac and run rsync, it runs for a period (sometimes more than an hour, sometimes less) and then gives me a ton of I/O errors. The image is stored on a RAID array, I am sure there are no I/O errors.

I think the connection with the Samba share may be getting overwhelmed... I've tried with AFP also, and I get the same result... What could be causing this and how can I resolve it? Or, any other ideas on how I can update the remote DMG file?