i've barely even dealt with animation in max, but i do know for sure that the .x format does support animation. every model/animation in Galactic Civilizations II is a .x file.
If nobody here can answer the question, go to I-Mod-Productions.com and talk to Stefan. He does a lot of .x animation.
Dave
If your using Panda exporter that could be why, I am exporting .x at the moment and panda doesn't seem to like animations. I have started using KW exporter instead and that's working fine with animation and textures.
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