The max exporter, XSkinExp.dle, doesn't seem to export skinned meshes, oddly enough, but exports physiqued meshes. However, the binary version downloaded from Microsoft's site crashes max when you try to do this with any animation in your model. The source code needs to be modified and the plugin rebuilt. You need the max sdk and character studio sdks for this. For max 5 users this may be a impossible because max 5 doesn't seem to come with a CS sdk. However, the plugin for R4 will work.
One thing I found out after hours of trial and error is that you have to collapse all texture modifiers (especially if you're using Unwrap UVW) before exporting, or the plugin won't generate the correct UV coordinates. AND max 5 has a nifty render to texture feature, but the plugin won't export it unless you convert it to an Unwrap UVW modifier. This isn't a one step process and involves saving the UVW mapping in the Automatic Flatten UV modifier, deleting that modifier, and then reloading the UV mapping into a new Unwrap UVW modifier, which you then must collapse into the mesh before you export the .X file.
Instructions on the source modifications to the plugin can be found here:
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grrr < . . > eetings
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