I've have the exact same problem myself (and never had a working version)... i've tried it with several different versions of mule (1.1.1, 1.2.0 and 1.2.3 are in my download area and i just tried those again, all of them do the same thing).
Im on ubuntu 9.10 with nvidia 190 drivers (i originally upgraded to the 190 drivers because this problem).
there was another post lying around about this too...
http://www.planetmule.com/forum?topic=439.msg2149#msg2149Im using sun java... though i've tried different versions without much luck... Chat works, just cant join/add ai at all.
Also worth pointing out that when i go to the settings dialog, i cant change the bound keys either. Maybe its a locale/input problem? UPDATE - actually, i just realised that unless i move out of the box where the key is typed, it doesnt actually update the key (so user problem). Though, thats the least of my problems really

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