There is no 3DSMax .smd importer. I know, I've looked (and used every search engine known to the net). I think there was one for version 2, but since I use 4.2, I wasn't able to get it working. If you're determined to find one anyways, there's MSN, AOL and Google.. You can use those to get best results (others have too many damn pop ups, and usually lead to the same places).
The only way to get .smds into max is the technique I mentioned above: use Milkshape to decompile the .mdl, import the referrence .smd (you need that one to look at any of the animations anyways, and it's the base model, so...) then export it as a .3ds, then import it with Max... After that, all you need is the .smd exporter to save your work (or do the same as above in reverse order... export as .3ds, import .3ds with MS3D, export to .smd)