Installing RHBA-2000:079-04 (glibc 2.1.94-3) results in most KDE2 applications failing with a segmentation fault (Signal 11). Notably, kmail will not start at all while konqueror will crash after a few minutes use.
I can't reproduce this. Make sure you're using the correct versions of KDE 2 and Qt (as found on ftp://ftp.linux-easy.com/pub/kde/rh7.0).
(Writing this from Konqueror...)
If this doesn't fix the problem, please supply some more information (such as a backtrace).