There seems to be a bug in kubuntu (Breezy 5.10) in holding the Gateway address in the Network Settings. When typing ftp or telnet at the command line I got an error messgae of: Network unreachable
I was still able to browse the web using Firefox etc but I was unable to use FTP or Krdc Remote Desktop (I also needed to apt-get install rdesktop before attempting this).
I was unable to get outside my own work subnet on our WAN.
Apparently this problem does not occur on Ubuntu/Gnome so it confirms that Kubuntu is more of a challenge (read buggy) at getting up and running but hopefully these issues will be sorted in Dapper.
This presented several critical problems to me but I found an answer on the web after struggling for a week or two with it. The answer was here:
http://www.ubuntuforums.org/archive/index.php/t-25915.html
and all I had to do was type at the command line:
sudo route add default gw xxx.xxx.xxx.xxx
The option of editing /etc/network/interfaces did not work for me.