You seem to be having some issues resolving the domain. Maybe your ISP's dns server attempted to resolve it at one stage, received an error and has stored that error for a while.
You could also try using the 'repair' option shown when you right click the network connection in your system tray, or by rebooting your computer/router (which may also be caching the dns error).
Anyway, you can connect by using the IP addresses below:
irc.wikked.us has address 69.64.50.139
irc.wikked.us has address 69.64.51.196
irc.wikked.us has address 69.64.39.137
Hope that helps