For some strange reason, my openSUSE 11.1 distribution seems not to be able to negotiate a DHCP Ethernet connection at home. Ubuntu 9.04 and Fedora 11 (live versions) are able to do that using the same computer and connections.
The only way it seemed to work was typing
dhcpcd -k eth0 and after that
dhcpcd -n eth0 (both as root). I don’t know what does it actually change, since I must keep that window open and the system considers that it isn’t connected.
It might be a bug, but sorry, too tricky to be reported.