Description of problem:
Until FC6, when one set a static IP, then switched to DHCP, the static ip was
disabled in GUI, but remembered between GUI restarts, so one could easily enable
the same ip or switch to DHCP.
Now static IP is forgotten after switching to DHCP and restarting GUI.
Workaround, create a copy of the device (one static one dynamic) and
enable/disable it (first column in the list view).