NASA and Lockheed Martin have agreed to a plan to go forward with the X-33 program, which includes an aluminum fuel tank, a revised payment schedule, and a target launch date of 2003. The X-33 was designed as a prototype to test the technologies that will eventually be developed into a replacement for the space shuttle. Unfortunately, problems with original composite fuel tank and a range of other problems caused serious delays to the X-33's schedule, and raising concerns that it would never launch. This revised schedule is 4 years later than the X-33 was originally supposed to lift off.

Original Source: http://www1.msfc.nasa.gov/NEWSROOM/news/releases/2000/00-284.html
Internet Coverage:
http://spaceflightnow.com/news/n0009/29x33/
http://www.spaceviews.com/2000/10/01b.html

See also: Securing space for the military