Motion Tween Problem

[Animadictsaiyuki]

I'm having a bit of a problem with my motion tween. I had already created tween and it worked, but when I moved the location at the end frame, instead of having a clean linear movement, it like bounces. I cleared it and recreated the tween many times but every time I receive the same error. Is there a perhaps a motion graph editor in Flash CS3 like in Maya has that I can go in and modify it or there's another way to fix it? Much thanks.

[edit]
I found the graph editor but it's at a constant. Strange for something where the movement isn't. :/