It's not actually a conf-file, its a gconf-key ;-) gconftool-2 --set /apps/fmms/exp --type int 1 should do the trick, and to disable it replace the 1 with a 0 EDIT: NOTE: this feature is REALLY experimental, and it might get you weird routes, occupying all the gprs connections and what not - a reboot should clear it in most cases thou (or a simple ifconfig gprs<N> down) in my experience...