This is true in the United States as well. That's why in every state, technically speaking, their is no crime of "rape" just varying degrees and types of "criminal sexual assault". I'm suprised that hasn't trickled down to france yet. Rape is defined as forcing someone to have sexual intercourse. It doesn't take much imagination to build an argument that you can't force a man to have sex, after all he had to get aroused. The advantage of criminal sexual assualt is that it side steps these kind of issues by greatly broadening the crime to basicly forcing/manipulating someone to engae in any kind of sexual activity.
"You get hard right now or I take this knife and cut your balls off sloooowly! You have one minute." That is probably out in left field. I doubt it would happen much.