Safari v3 (Leopard) vs. v2 (Tiger) compatibility problem

We are in the process of replacing our client machines with new ones. Our current environment is Tiger using OD and all home directories are network mounted. The new machines, of course, have Leopard on them which uses Safari v3. When I try to launch v3 it obviously is using the preference files from the home directory that were create by v2. I am guessing this is the crux of my problem which is that v3 will not run, it just bounces on the dock and has to be force quited. So my question is, has anyone encountered this problem and how do I resolve it? TIA.