Upgrade to Hoary: problem starting Gnome

[CB]

Gnome fails to start for me after the upgrade. My .xsessions-errors file 
contains:

/etc/gdm/PreSession/Default: Registering your session with wtmp and utmp
/etc/gdm/PreSession/Default: running: /usr/bin/X11/sessreg -a -w 
/var/log/wtmp -u /var/run/utmp -x "/var/lib/gdm/:0.Xservers" -h "" -l 
":0" "<username>"
/etc/gdm/Xsession: Beginning session setup...
Failed to start message bus: Failed to read directory 
"/usr/local/share/dbus-1/services": No such file or directory
EOF in dbus-launch reading address from bus daemon


Of course there isn't a /usr/local/share/dbus-1/services, but there is a 
/usr/share/dbus-1/services/.

I don't know anything about how Gnome starts up: any idea where it might 
be getting this mistaken path from?

Btw, I can start Gnome if I choose the 'failsafe'-type session.

Cheers,

CB.