http://www.boeing.com/news/releases/2003/photorelease/q3/pr_030918g.html

Boeing is proposing the new B717-300X, which would be138.3 ft. (42.2 m) long, compared to 124 ft. (37.8 m) for the -200, and would carry 130 passengers in two-class configuraiton. The -300X would have higher maximum take-off and space limited payload weights, and greater engine thrust than the -200. The -300X also would have a service door behind the wing.

If launched, delivery of the 717-300X is targeted for the second half of 2006.

It is believed that such decision is urged by Air Tran, which operates mainly B717-200 and wanted larger derivatives of B717 of longer range, to serve routes with more passengers, as well as longer routes.