CHECK IT OUT:
I have a POTC2 game on my Verizon cell phone.
It tells this little story with the game.
I have gathered from it that:
Jack was the captain of a ship named the Wicked Wench. It was sunk by the (British? East India Company?).
Jack made a deal with Davy Jones. Davy Jones raised the ship from the depths of the ocean and gave Jack 13 years to captain it, in exchange for 100 years of service from Jack.
Jack agreed, and DJ raised the ship... which Jack renamed The Black Pearl.
I'm not sure how credible it is, but all of the other information in the game was correct....