Ultima Online Five on Friday Q&A

EA's Jeremy Dalberg has posted another one of his "Five on Friday" Q&A features on the official Ultima Online website.
"Why did mage cast times get nerfed with this patch?"

So, the change was this: instead of rubberbanding when you try to move when you're casting (as in, your character moves a couple steps then "snaps back" to its original spot) you actually stay in one place for the duration of the cast. This is purely a client-side change - the server has always handled casting this way. You're now just seeing what's actually happening, rather than what your client guesses might be happening before the server tells it otherwise.

It will take some getting used to for mages, certainly, and it's possible that certain applications of low-cast-time-spells might be slightly affected, but overall this is a step in the direction of making the movement code less susceptible to certain types of attacks.