The simplest solution is to ssh -X xterm instead of gnome-terminal
since xterm doesn't desperately need to talk dbus like every
gnome application.
The complicated solution is to run a script rather than
a simple gnome-terminal command and have the script
do something like:
#!/bin/bash
unset DBUS_SESSION_BUS_ADDRESS
eval `dbus-launch --sh-syntax --exit-with-session`
exec gnome-terminal
That will create a new dbus session on the remote
side for the duration of the gnome-terminal
(but I haven't actually tried this :-).