while trying find out, why sip-router produces mysql "out of sync"
errors, i discovered that msilo m_dump only recognizes that register
request is un-register request, if it has expires header with body 0.
it is not checking if contact header has expires=0 parameter like this:
Contact: <sip:jh_test_fi@192.98.101.10:5074;transport=udp>;expires=0
-- juha