I take it hat this service is 'Doku CS' (23.5E 12109H 27500 3/4 8PSK)?
If so, that service broadcasts indeed in 4:3.
But: all VU's have a bug in this respect: for this specific service (and there are some more) you can change the lay-out, by changing the setting for 'Display >16:9 contents as'. The GUI shows this service as being 16:9. Strange as that may sound, it works.
On other brands it works as it should (i.e. in 4:3 and marked as such).