You are correct - knockback does indeed only send you in one direction on the emulator. I had coded a quest file for Sugal the Fist.
On live, if you hailed him and were not a froglok, you'd get "The Fist STRIKES!!"; 2 points of damage and massive backwards knockback.
First actual fun I'd had on everquest in ages. I spent at least 10 minutes messing around to see where I could end up and always went back when I was in the zone
On the emulator, it is same direction, every time. I assume the spell needs a direction to come from somewhere other than the client. I was playing patched DoD at the time.
Bleh. Just looked and I can't find the file I wrote.