Lasy year I tried to grow Passiflora edulis, using seeds from Morrison's 80p passion fruit. They sprouted without difficulty, and grew well in pots indoors, but when I moved the pots into the garden for the summer they barely did anything. They have not completely died back over the winter, and may well revive come spring, but I am not convinced that I will ever get edible fruit from them.
Incidentally, for the scientific-mind (and not for those of a queasy disposition), those seeds that were recovered after passing through the human gut were roughly twice as likely to germinate as those that were harvested straight from the fruit ...
** Phil.