I've got my SAIL server up & working & all seems fine (.. pretty damned fine, actually

). Just one small question:
I've registered with Gradwell & have set up a trunk to recieve incoming. I can also set up outgoing, but only by putting the following in a custom app:
exten => _0.,1,SetCallerID(My_Number)
exten => _0.,2,Dial(SIP/${EXTEN}@sip.gradwell.net)
Where My_Number is the CLI number I've registered with Gradwell.
I'm guessing its the SetCallerID that's failing when I try to do this through SAIL using a route & trunk. Is that right?
Its not a big problem - it would just be nice to do it all through the SAIL options if poss.
Cheers
Jon