Found this randomly when poking around the Internet Movie Database: Raging Bull II. Per the proposed synopsis:

A unique combination prequel and sequel that explores "before the rage" and "after the rage" of world middleweight boxing champ Jake LaMotta's tumultuous life and times.

Raging Bull II is currently aiming for a 2010 release date. Hopefully, the multiplex in Hell isn't already booked by Transformers 3.

This article appears in Jun 24-30, 2009.