Beginning April 1, 2011, the U.S. Department of State will require the full names of the applicant’s parent(s) to be listed on
all certified birth certificates to be considered as primary evidence of U.S. citizenship for all passport applicants, regardless of age. Certified birth certificates missing this information will not be acceptable as evidence of citizenship. This will not affect applications already in-process that have been submitted or accepted before the effective date.
http://travel.state.gov/passport/passport_5401.htmlMaybe the new requirement is to prevent parents from getting a passport for the kid in order to take them out of the country without the other parent's permission or knowledge ~ custodial kidnapping.
