July 1,2009 CBP (Customs and Border Protection) notifies that all Visa Waiver Program emergency or temporary passports must be electronic passports.  Only travelers holding these E-Passports will be able to travel to the USA under the VWP.  Passports that do not comply with this regulation  (with the exception of those that are traveling for emergency reasons and have been given discretionary approval) may be detained for processing and may potentially be denied admission to the USA.

We link to the CBP website for more information.