E36 320i Alarm/immobiliser help please!

[gumballer]

Just bought a 320 off a friend who told me all about the troublesome alarm, and today it took me 10 mins to get going, it basically plays up and locks you in the car, then sets off the alarm, it takes numerous goes to get it going and if it wasnt for the fact that the rear windows are wind down then you would be stuck in the car!

BMW say they cant disconnect the alarm immobiliser, does any one know anyone who can or have any suggestions or previous experience on this?

help!