If you have a domain like http://www.vanlisdonk.nl or http://www.roelvanlisdonk.nl and host these websites on you’re own server. The websites will show the router admin page from inside you’re network.
Changing the windows host file in C:\Windows\System32\drivers\etc, routing the internal ip adres lets say 192.168.1.55 to www.vanlisdonk.nl solves the problem.

The host file on all client pc’s on you’re internal network should look like this:

See:
http://www.howtoforge.com/forums/showthread.php?t=12475