I'm pretty sure it's a Philips, but I don't know the model number. It's nowhere on the unit and it's not mentioned in the manual. I think I'll go and pay the dealer a visit and ask him.

I did find this however. The technical details show it's using a "Renault fitting adaptor" and not an FM modulator, so it must be possible!

A bit of digging around on this site showed me this. (look under Renault, Philips headunit)

Now of course I still don't have any idea if this will work with anything different from a Denison unit, but I think my chances are pretty good.
I would love to see a picture of the back of a Denison unit now, if only to see if it has a special interface of it's own (in which case I would be out of luck), or if it simply uses cinch. I've looked for the Denison homepage, but it seemes to have vanished. Nothing can be found online about this player anymore, except for one review with little or no photo's. Has the Denison been discontinued?
Could anyone provide any more info about this?

Thanks!