I can't get WebDAV working


I followed the instructions on the Wiki and have fooled around since then and I still can’t get it working.

Using the control panel, I enable a directory as

http://www.mydomain.net/ (directory goes here)
Enable WebDav
Throw in a user account, hit “change these settings”… and nothing.

I can’t connect from OS X using clover-K to connect to a server (“You cannot connect to this server because it cannot be found on the network…”) or WinXP (standard XP lame error messages go here).

I’ve tried:
toggling password protect on and off
toggling WebDAV on and off
trying to enable webdav on a different directory
taking a break and having a beer
repeating steps 1-3

I don’t know what else to do at this point - is there something amazingly obvious I’m missing?