After the IVR choice is made, but before your Grandstreams are Dial()'ed
add the following:
exten => s,n,Set(CALLERID(name)=${CALLERID(name)}#Sales)
;and
exten => s,n,Set(CALLERID(name)=${CALLERID(name)}#Support)
I used the ‘#’ character as a seperator, you can play with that. Maybe this is better for you:
exten => s,n,Set(CALLERID(name)=Sales:${CALLERID(name)})
;and
exten => s,n,Set(CALLERID(name)=Support:${CALLERID(name)})
Since most Caller*ID data is limitied to 15 characters, the Grandstream 2000’s can handle longer strings, so you should be good to go.