exten => *98,1,Answer
exten => *98,2,SetDB(mydnd/selected)=1)
exten => *98,3,Hangup

exten => *97,1,Answer
exten => *97,2,SetDB(mydnd/selected)=0)
exten => *97,3,Hangup


exten => 1,1,Answer
exten => 1,2,Gotoif($[${DB(mydnd/selected)}  = 0]?3:4)
exten => 1,3,Dial(SIP/1,30)
exten => 1,4,Voicemail(1@default)
exten => 1,5,Congestion)
exten => 1,6,hangup