Check out this article: http://www.foodallergy.org/press_statement.html
FAAN (Food Allergy and Anaphylaxis Network) advises not eating them at this
point.
McD's apparently claims "well, the ingredients are 'derived from' milk and
wheat but don't contain any allergens" which is possible (theoretically, one
could make a safe ghee, for example).
--Robyn