[Asterisk-Users] How to set busy

[Miles Scruggs]

For multiline phones how do you set SIP channels to busy.  For instance 
if SIP/101 is on a call then dial would return busy.  Right now it just 
starts ringing on line X, and stacks up from there.

What would be really great is if I could control how many calls by the 
context.  So if a call was routed via

[overload]  Then the ext wouldn't report busy it would just keep ringing 
available lines, but if the call was routed via

[singletrackmind] dial would return busy if the channel already had one 
call.

Thanks

Miles