exten => 810510,1,Answer
exten => 810510,2,agi,availability.pl
exten => 810510,3,Hangup

exten => 810511,1,Answer
exten => 810511,2,agi,availability.pl
exten => 810511,3,Hangup

exten => 810512,1,Answer
exten => 810512,2,agi,availability.pl
exten => 810512,3,Hangup