i've installed gimp and wireshark from macports. these apps ran fine on 10.4, but upon upgrading to 10.5 they don't run more than a minute or two without raising a fatal X11 error. a number of other users experienced difficulties with 10.5.0's X11, but i haven't heard anything since then--whether it's a client or server problem or what. i did try recompiling wireshark after installing 10.5, and also 10.5.1, but admittedly beyond that i haven't looked too deeply into the problem.