Sorry to hear about your trouble with the long word wrapping. I know that is frustrating!
Unfortunately, this is a "native" behavior of HTML. Long words that do not have any spaces or "break characters" cannot be wrapped. The solutions are either:
A) Before binding your data, "clean" it with code that inserts spaces at specific intervals so it can be property wrapped
B) Let the text "overflow" in to a hidden area (the approach RadGrid provides automatically)
For more discussion on this HTML issue, check out this discussion on Stackoverflow:
Hope that helps!