The url looks fine. I hade the same problem in the begining, I don´t know what the problem is, but mine dissaperd after I reconfiured the server with turning the webmail off and then restarted, then reconfigured again switching it back on. If that had something to do with I don´t know but after that it worked, in the back of my head I have a small memory about the webserver not accessing through the domain but work fine with ip, so maybe I did something else aswell. But it all was done with reconfigure and restart.
/ron