SetCallerID( ) Sets the Caller ID for the channel
SetCallerID(clid[,a])
Sets the Caller ID on the channel to a specified value. If the a argument is passed, ANI is also set to the specified value.
Always returns 0.
; set both the Caller ID and ANI
exten => 123,1,SetCallerID("John Q. Public <8885551212>",a)