I am also trying to export models to three.js format (json or objectloader), but it doesn't seem to include animations (animations property is ). I do have other models in json format that does include animation, so three.js definitely supports this now. Maybe the above reply is outdated? Is the exporter still lacking this functionality? I have not had any luck with exporting the animations using the collada format either, but will keep trying with that.
EDIT: I tried collada as suggested, but it doesn't seem to include animations either. I could open the exported collada file in both 3ds and blender, but none of them had any animation on the imported model. Are there any extra steps needed to get animation data exported with the model?