for bro keane,
my mechanic can repair gearbox. but he says e46 gearbox parts are hard to come by. according to him, your problem could be a faulty torque converter switch at the gearbox itself. this shouldn't cost much.
he is located at optimum auto at kg kayu ara, near nkve dsara toll and centre point, pj. do pm me for directions if you are keen.
chew