That's because it's essentially a redesigned MD-80/DC9. Boeing and McDonald Douglas merged in 1997 as the "MD-95" was about to go into production and it was released as the B717. It ceased production in 2006. Sales were poor, in large part because it didn't have operational commonality with either any Boeing product or any MD product (although it looks like a DC9/MD80, someone who was current in the DC9/MD-80 didn't have a "type rating" in the 717)

http://en.wikipedia.org/wiki/Boeing_717


RFTraveler