DH,
Well good luck! At least you no know more about RNP procedure design than you ever hoped for Keep us informed on what happens, of course now we all want to know!
He's an operator like me and sitting in the cockpit before departure my only concern is CAN or CAN'T I fly it?
If you had approval, you wouldnt be sitting there wondering, you would already know.
As far as the A340-300, sure it can be RNP capable. If that particular airline ordered enough equipage, or if the certs have been maintained, there is no way for any of us to guess....
In the US, it has been difficult for the airlines. Many of them spent quite a bit of money getting equipped, certified, and trained, only to find out they seldom get to use RNP. Just as with alot of the CATIII ILS, the airlines are letting the calibration, certs, and recency expire, to save money on costs.