For example xterm does not have the --sm-diable option so you cannot start it that way. It is possible to start network-admin --sm-diable though to reset the network configurarion to a working state.
gnome-session might hang because of a non-working network environment, see bug #49431 -- Unable to start applications after hibernation https://launchpad.net/bugs/49221 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
