Not sure about that, even if you mean for just ULib itself.
My belief, which very well could be wrong, is that when an error occurs, that section of Lua stops being executed.
I think there would need to be an extra Lua "wrapper" of some sort to anticipate any error much like the engine already reports them.
I can't find any Gmod wiki documentation, nor could I download the release when I attempted to, but you may try checking out MrPresident's release ALog to see if the ServerLog command can log Lua errors in any way.
http://forums.ulyssesmod.net/index.php/topic,3890.0.html
