Has anyone come up with verification of this? Not that Obama went, but that it was not allowed for US citizens at the time? I've looked and can't find anything that says that other than these sorts of assertions.
http://texasdarlin.wordpress.com/2008/10/21/bombshell/#more-4155
This gives the outline of the lawsuit being filed with the Federal Government by Attorney Berg (challenge of BO’s citizenship).
http://community.mccainspace.com/kickapps/_Obamas-trip-in-Pakistan-1981pakistan-under-marshall-law/BLOG/119997/41158.html