I would guess that you used gnome with redhat, and KDE with SuSE? I think SuSE defaults to KDE... the name GTK Gnutella suggests that it's a gtk (gnome) app, which could explain problems running it in SuSE (if you use KDE). Still, i've never had any real problems running gtk aps in KDE, they run better than qt apps in gnome. You could try limewire, and you could also try running windows p2p apps like kazaalite and winmx under wine, i've heard they work ok.
overnet's kind of like a dodgy port from windows though isn't it? also it is limited in what it has to offer in my experience. i prefer gtk-gnutella, they are the only two i have ever seen working properly under linux, not that i have much patience getting these file sharing programs to work, so maybe somebody who actually puts in the effort to do the p2p file sharing thing should/has put in the work to figure it all out.