Hello, Thanks to the list for your help. I can say that SER is running OK and we are doing a lot of very interesting tests. I have a question about contacts. As Jiri said to me, SER sends all contacts in replies to REGISTER. This reply is a 200 OK and has so many Contact fields as the user has in database. The problem is that SIP clients like Windows Messenger doesn't care about this Contact Fields. I know this isn't very important if you're thinking of SIP Phones, but we are very interested in presence. We work with SIP applications which need to know about user's contacts from database. So, I would like to know if someone has tested a SIP software that works on this issue. We have looked at RFC 3261 about this, but there isn't any comment. Thank you very much Curro