Lingering "ghost" hotspot

I’ve got a movieclip with rollOver and rollOut code on it (it’s acting as a button). In a nutshell, the rollOver makes the graphic wider, and the rollOut reduces it back.

All the animation is fine. The problem lies in the hotspot. The first time you rollover the button, everything works just fine. The hotspot extends with the stretching of the graphic, so you can still move the mouse along the stretched graphic without it shrinking again.

After rolling off the graphic and letting it shrink, though, there is a “ghost” of the stretched hotspot. So even though the graphic is back to being a little square, there is a long rectangle of hotspot area that activates the animation again.

Anybody ever had a problem like this with dynamic hotspots? Thanks for any help.