From Premiere Magazine:

Diesel's Unfinished Business

Why is New Line sitting on his two-year-old film, A Man Apart?

Vin Diesel has proven his action hero mettle, so why is New Line sitting on its two-year-old Diesel starrer, A Man Apart? The action flick, about a drug lord named Diablo (Timothy Olyphant) and the DEA agent (Diesel) sent to take him down, was conceived as a franchise, but the studio has bumped the film's release date four times and discarded two titles. (The original title, Diablo, inspired a lawsuit from the maker of a identically named video game.)

The main reason for the delay is that, some 18 months after the picture wrapped principal photography, New Line is still wondering if the $31 million film would benefit from a different ending. But with director F. Gary Gray currently shooting The Italian Job, that would mean hiring another helmer (possibly 15 Minutes's John Herzfeld) and scheduling a star who's even busier than he was two years ago. Then there's the money: a reshoot would cost the studio an extra $3.5 to $5 million. Regardless of what New Line decides to do--tinker or take its chances with what's already in the can--A Man Apart is scheduled to hit theaters this April.

From Corona's Coming Attractions:

An anonymous insider we know well tells us that the ink is dry on the shooting dates for The Chronicles of Riddick. The movie begins its first day of principal photography on April 21, 2003 and is scheduled to wrap filming on August 31, 2003. Filming is still scheduled to take place in Vancouver, Canada.