In my experience this is a very easy one to germinate. About 90% came up for me. Any light soil will do but give them a lot of heat and don't let the soil dry out. It will usually self-pollinate too so you should get plenty of fruit.

Here is a link that might be useful: Seed tips

I've used anything from seedling mix to just plain dirt from the yard.

The big things as Myles said are water & heat. Don't let 'em dry out but don't drown them either.

Passies can take anywhere from a week to over a year to germinate. About 3 days after you recycle the dirt... That's when they'll sprout. All the sudden you have a bunch of seedlings... And absolutely no idea what they are. Or the name has worn off the tag.
I take aluminum flashing, paint one side black & scratch the name into it with a carbide scribe. (anything hard & sharp will work tho) that way I'll never loose the name.

I guess the bottom line is this: Never give up on 'em.