This needs to be addressed in Firefox really. Either it should handle mimetypes properly as per XDG spec out of the box or at least use xdg-email to invoke $emailclient.
IIRC latter is the only sensible possibility as the mimetype handling requires a lot of GNOME libraries. So I suppose firefox should invoke xdg-email unless GNOME integration is available.
This needs to be addressed in Firefox really. Either it should handle mimetypes properly as per XDG spec out of the box or at least use xdg-email to invoke $emailclient.
IIRC latter is the only sensible possibility as the mimetype handling requires a lot of GNOME libraries. So I suppose firefox should invoke xdg-email unless GNOME integration is available.
Moving bug to firefox-3.0 source package.