[macro-user-callerid]
exten => s,1,DBget(AMPUSER=DEVICE/${CALLERIDNUM}/user)
exten => s,2,DBget(AMPUSERCIDNAME=AMPUSER/${AMPUSER}/cidname)
exten => s,3,GotoIf($[foo${${AMPUSERCIDNAME}} = foo]?5) 
exten => s,4,SetCallerID(${AMPUSERCIDNAME} <${AMPUSER}>)
exten => s,5,NoOp(Not changing CID)