I've never heard that problem before.
First things first, check your Feedgator setting and make sure that XHTML clean is set on (value of 1 in the database field). This will scrub your incoming code and help display it properly in Joom's.
Secondly, try switching your template between a few various ones and see if your template may be causing a problem.
If that fails... PM me, and we'll work out a way to get you helped
