Framerate issue - IE vs FireFox

My flash .swf file is set to 120fps.

Watching the movie in the flash player (double clicking the .swf) will cause the file to play at 120fps.

Watching the movie in Internet Explorer will cause the file to play at what appears to be around half speed (60fps)

Watching the movie in Mozilla FireFox will cause the file to play at 120fps.

Why does IE half the FPS of the movie? It’s not the graphics/animations/cpu or gpu utilization. It’s has nothing to do with what mode I publish the html file in (window, transparent windowless, etc). It almost seems as if IE has capped FPS at 60.

Does anyone know why this happens? Or how I can fix it? Is there a way to force IE to play it at 120fps?