It will probably confirm eventually, but it could take several days.

I haven't had much luck running pywallet on a Mac.  You could manually build a new wallet that doesn't include the transaction by using importprivkey, but it would be a lot of work, and probably not worth the effort.

If it hasn't confirmed after a few days, you could import just the private keys associated with that particular transaction and create a raw transaction spending the same inputs but paying a transaction fee.