On My Project With No Name (LOL) I Need Some AC Help :(

I Have Drawn A Up And Down Hill Sloping Ground, My Problem Is When I Make My Character Move Up It He Just Walks Into It, And Then When I Tell Him To Jump, He Appears Ontop Of The Ground He is Inside.

Any Advise // Actionscipt Problems?

My Characters Actionscript Is:

onClipEvent (load) { moveSpeed = 10;}onClipEvent (enterFrame) { if (Key.isDown(Key.RIGHT)) { this._x += moveSpeed; } else if (Key.isDown(Key.UP)) { this._y -= 0; } else if (Key.isDown(Key.DOWN) && !fall) { this._y += 0; } else if (Key.isDown(Key.LEFT)) { this._x -= moveSpeed; }}onClipEvent (enterFrame) { if (Key.isDown(Key.SPACE) && !jumping) { vel_y = 36; jumping = true; } if (jumping == true) { vel_y -= 2; if (vel_y<=-15) { vel_y = -15; } this._y -= vel_y; } if (_root.ground.hitTest(this._x, this._y+35, true)) { vel_y = 0; jumping = false; }}onClipEvent (enterFrame) { this._y += 16; if (_root.ground.hitTest(this._x, this._y+1, true)) { this._y -= 16; }}

And My Ground Simpally Uses A Instance Named ground

Any Suggestions?

Alex