If you're talking Eclipse plug-ins and things of that nature, then no, I'm not aware of any... then again, I'm not a fan of IDEs in general, so why *would* I be aware of such a thing?!? LOL
In general though, repeast after me: Firebug is the Way and the Light. If you're doing modern web development and NOT using Firebug, you either (a) have something *much* better that the rest of us are not aware of, or (b) are mildly insane. I'd bet on the later
If you do use an IDE that has both client-side and server-side debugging capabilities, then that would probably help for DWR too, but failing that, Firebug is the way to go.