The GNOME launcher gets very grumpy when your host name changes. I am in a DHCP office, and when I plug in the laptop and establish a connection, the laptop gets a hostname. DHCP assigns a hostname based on the in-addr for the IP address it was allocated. Well, if you are already in the middle of a GNOME session, you can forget about opening any new Gnome Terminal windows. (I have noticed this problem in KDE, as well, but I don't use KDE, so I won't report the bug. ) You don't even need a DHCP session in your office, just launch a window, type hostname newhostname, and try to open another window. Other programs don't launch either. Xterm is unaffected.
The best solution for this is to decide on a hostname (which doesn't need to exist on any real network) for your machine, say my.machine (which will work fine). Edit /etc/hosts, and put "my.machine my" on the 127.0.0.1 line, and set your hostname in /etc/sysconfig/network. We're working on a better solution.