I saw the same problem this morning, determined it was wxallowed required on /usr. After updating /usr mount with wxallowed Python build continued.
I decided to search ports mailing list to see if anyone else had the same issue, stumbled across this thread. I installed 6.1 from ISO I downloaded right after 6.1 release announcement. I used installer default partition settings. I did not create a new partition for ports, so it is a directory on /usr. As Adam stated perhaps an update to faq15? diana
