Thread:Project:Support desk/Upload and Save Page redirects to local and not external domain/IP

On any external machine, when I upload files or save edits to my wiki I get redirected to the local IP address of my server on the network (e.g. 192.168.x.x), which gives me an error. How do I permanently disable the change of domain name? I have already tried to edit the /etc/hostconfig file, as is specified here.

I am running the version 1.18.1 of MediaWiki, 5.2.15 (apache2handler) version of PHP, version 3.3.7 without full-text search support of SQLite, and hosting from Mac 10.5.8 (Client) via Websharing for Apache. I am also using Port Forwarding.