Minimo,
I don't have a solution for you, however, I did just receive some Examiner guidelines for the new process from 2008 which I have not digested as yet.
Give me a couple of days to look at it and make some enquiries.
Logic says to me that if you are operating on a French Licence then the French Authorities should be responsible for your language endorsement. I doubt a British CAA FRTOL will help you.
I will look into it.
tam