Cannot delete network devices in Fedora Core 2

I am clicking on the little Red Hat > System Settings > Network.
There are tabs for Devices, Hardware, DNS, and Hosts. I can modify
the Hardware items just fine. My problem is when I make changes to
the Devices. I have more devices setup than I would like, due to some
previous testing. The devices are named like eth0, eth0:1, eth1,
eth1:1,.... I delete some of these by highlighting them and clicking
delete. They disappear, but every time I come back to the network
configuration gui, they are back in the list....even if I reboot. I
have this same problem on my laptop, and desktop. Has anyone else run
into this? Am I doing something wrong? Does anyone know how I can
fix this? Thanks.