Did you change any of the "preferred applications" via the menu (or via
the cli-command "gnome-default-applications-properties").
If so this might be a duplicate of:
https://bugs.launchpad.net/ubuntu/+bug/800927
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Desktop Bug
Same behaviour here.
It worked well under dapper and only became broken after an upgrade to
edgy.
Under dapper i was still required to enter the admin password whenever i
wanted to change time-settings using the [Time-admin], in edgy however
this is no longer required.
Therefore i suspect it has
