RonO,
May I also point out that in November 2003 a supplemental contract was awarded to Lockheed Martin, valued at US$603 million, covering the development of an "international partner version" for the JSF, including "a version of the JSF... that is as common as possible to the US air system within the National Disclosure Policy". And the wording used by JSF programme officials when questioned about it at the time finds a worrying echo in Burbage´s answer.....
Iinternational Defence Review, May 2004: "a JSF program official said that the export versions "would look the same" - implying that materials under the surface might be different. Another source says that "all JSFs will have stealth features" but will not confirm that all of them will be identical in LO performance."