Right now, if you install PHP, or something dependent on PHP, from pkgsrc, you get PHP 5.3.  The default for pkgsrc will move to 5.4, though I assume that’s going to be after the pkgsrc-2013Q1 release scheduled for the end of this month.  I don’t know the upgrade path, but it sounds like 5.3 is on the way to retirement, in any case.