[Asterisk-Users] BUSY-tone on incoming calls?

[Daniel Nyström]

Is it possible to make the telco send an busy signal when an incoming call are supposed to dial a group which has all lines busy?
Since I will get many public phonenumbers into my E1 (from telco), it will be sliced up into a few groups. There might be channels availible in the E1, but not on the other side of Asterisk (the office side).