This relationship is symbolized through a couple of people in France, the beautiful Cécile De France, playing Clara, a young Jew physio, and Zem himself, playing Ismael, an Arabian pianist. Both of them are nonpractising, but will have to face the reactions of their family and friends when wanting to make their love official.
First, the film really is a comedy, although dealing with this problematic theme. This is, I think, a good choice, considering the weight of the current developments, particularly in France. But making a "light" film was not the aim: as already said, Roshdy Zem is an engaged actor(cf. Ingigènes recently, or most of the films he played in). The director indeed is a real humanist, and has always fought for this concept of equality and fraternity, pretended basis of french society. That is why he uses derision and humor to stress the incredible tensions a love affair between two not-religious people can create because of their inheritance.
So, the film is nice and beautiful, etc... But because of its theme, it had to make people think and react, which is not allowed by an useless happy end (the one minute too long), probably imposed by the production. While during all of the film, Zem shows the difficulties caused by this difference between the two characters, the end totally dilutes it, showing a great agreement. Of course, this is only the story of two particular people, but the uncertainties seen in Clara's and Ismael's eyes in the before-last scene would have given the film a more symbolist and universal end.