AE = Angle Eject.
Straight from Yahoo Answers:
"Early 94s would eject the spent shell casing straight up. Pretty hard to put a scope over the gun when the shell casing does that! However, there were a number of side mount scopes that would be offset to one side or the other, depending upon if you shot left or right handed. Pretty easy to break when they stuck off to the side and if you loaned the gun to someone who shot opposite hand, they were hosed.
"However, Winchester fixed that with later models, starting in 1984. They have "angle eject" and shoot the cartridge off the the side. Just see if your Winchester is a later model made since 1984 and if it is, you should be able to mount a scope over the center line without a problem. There are a number of scope mounts you can chose from."