Earlier quoted context omitted.
If you're allergic to something and you tell a waiter to just bring you anything I think you have about 100% of the responsibility all by your lonesome and if you sue the restaurant from that situation I sincerely hope that you not only lose but will be forced to cough up the legal fees for the defending party.
I'd like to think you are correct, but (at least here in the United States) I can see the lawsuits piling up. People here sue over spilled coffee, it's not out of the realm of possibility.
http://en.wikipedia.org/wiki/Liebeck_v._McDonald%27s_Restaur...