[Xquartz-dev] Where does xquartz write it's DISPLAY variable

Hi! I've installed latest xquartz alpha 3 on Snow Leopard and then 'uninstalled' it via deleting /opt/ and the .app. Now I have problems, because my DISPLAY variable is set to /tmp/launch-ANUPoX/ org.macosforge.xquartz:0 instead of ":0". In which file, does xquartz write this configuration? I've tried adding 'export DISPLAY=:0' in various config files, but 'getenv' in Emacs still returns the xquartz setting. Regards, Ziga