Facebook sending unauthorised friend request

Recently, FB sent a friend request using my account without my knowledge. I tried to complain to FB, but there is no way I could do that. facebook.com/help takes you to a forum where many people have already vented their anger at this antic of FB. I talke to friends and practically everybody confirmed that this has happened to them also.
Is there anyway one can stop FB from doing this cheap trick of increasing their networlk? This is invasion of my privacy and is embarassing when friend request is sent to a relatively less known person.
Is there any solution at all , short of discontinuing FB account? Is there anyway one can let FB know of user grievances?

Thanks n Regards
Shekhar Nargundkar