[Serusers] msn presence

just some q's, how is the registrar related to usrloc? does it look up the mysql ul db? msn messenger 4.7 fails to detect the presence status of a user, i did a network dump but couldn't find any trace i'm not too sure if my understanding is correct but if the pa receives a subscribe, it checks registrar then sends a 200 ok then a notify containing the status in the sdp. is this right? the sdp content of the message always show "closed". how about msilo? in the previous release of ser, my msilo works, now i had trouble storing and fetching. and i noticed something, when the caller hangs up while the other phone's still ringing, i could see the "bye" from messenger but ser doesn't proxy it to the other party. so the other phone continues to ring. is this because ser expects a "cancel" rather than a "bye"? ~kelvin