i'm experiencing exactly the same thing, and the worst part is im not even using a mac :-S
i've tried running PMS in different 3 virtualized Windows's, and no matter what i do, the same error
The error pretty much came out of nowhere...it used to work fine.
(sorry about being a dick and posting the wrong section, but it does seem to be exactly the same error....see
viewtopic.php?f=6&t=3150&start=10#p14789)