It can't be done via the obd port,ecu has to be removed and drilled,i believe DMS have done one,But the guys over on baby bmw are getting as good a result using a tmc tuning box id go the tuning box route,it's a lot less hassle and offers strong results..
BW Chiptune may be able to do this via the OBD where others can't. He isn't as 'big' as the likes of DMS but gets good write ups for BMW's. I believe he is in Hayes or thereabouts.
