On "yum update [some stuff here]" to rawhide from FC3-something-or-other, python was upgraded (2.3->2.4 I think) which meant that yum was missing required deps (sqlite and urlgrabber). This is the _old_ yum that requires these and they were pulled from under it, I think. Just the standard problem with splitting up a package more than it was previously. Don't know if there's anything we can do or not.
yum has a requires on urlgrabber and sqlite. If you do only some stuff, then you probably got python updated and not other bits (including yum) because we don't have python deps everywhere we should (although we're doing better with what's in FC4).
Until we get real dependencies, not really something we can address.