Animation of displacement mod lost when it's applied?

I have animated a cloud texture on a plane using displacement modifier. It works for animattions in Blender. I want to export the meshes to direct X. If I apply the modifier it only affects the frame I’m on and the animation no longer happens. Is there a way to get the displacement to remain animated after it’s applied? I used an empty object moving with an ipo curve as the object the texture is mapped to to achieve the look of the texture changing.

Thanks,
Chris