ab72.cfg
ab76.cfg - t_check_trans for ACK and for CANCEL, $si and $Ri checked against regex ...3 and ...4 IPs
ab77.cfg - listen=...4
ab78.cfg - one loop detection block for ACK and CANCEL requests
ab79.cfg - memlog, server_signature, sip_warning
ab80.cfg - $var(rr) is computed in route[10]
ab81.cfg - the same
ab82.cfg - logging is done from route[11]
ab83.cfg - almost the same 
ab84.cfg - logging call start and stop records (200 OK of invites and byes)
ab85.cfg - almost the same
ab86.cfg - adding $Ts to each log record
ab87.cfg - ACK and CANCEL: t_relay() if t_check_trans() and abandon otherwise
ab88.cfg - call stop is also BYE and not only 200-ok of BYE