I've seen the odd post previously about the Zoom 5800 ATA but nobody's posted a comprehensive set of settings. I've got a Zoom 5800 ATA and I've hacked into it with the administrator password but I can't seem to get the right SIP settings. I think some of the problems may be to do with getting to it through my router but even when I change to a different router and put the Zoom 5800 in its DMZ (and give it a static IP) I can't get it to work. I did get as far as getting a dialling tone once (but I'm not even getting that now) but when I dialled a number I got a fast kind of tone (even though the other number definitely wasn't engaged) and the number I rang didn't ring. If anyone could send me screen dumps of their successful Zoom 5800 setup I'd be really grateful. You can e-mail andrea at allaboutresources dot co dot uk Thanking you.