exten => 222,1,Set(MEETME_EXIT_CONTEXT=addmember)
exten => 222,2,MeetMe(9000|srX)
exten => 222,3,Hangup()

[addmember]
exten => 1,1,M(getdigits)
exten => 1,2,Originate(local/...)
exten => 1,3,Meetme(conference)