Project: Blender Extensions
Tracker: Py Scripts Release
Script name: io_scene_ms3d
Wiki page: http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Import-Export/MilkShape3D_MS3D
Author(s): Alexander Nussbaumer
Category: Import Export
SVN Download: https://svn.blender.org/svnroot/bf-extensions/trunk/py/scripts/addons/io_scene_ms3d/
this add-on allows you to import ms3d files to Blender and export ms3d from Blender (conform with MilkShape3D v1.8.4 file format).
at import time, all properties of the ms3d model will be stored to separate MS3D-panels in blender to have nearly 100% control of all the available raw data. same for export. the exporter will respect the data, that are stored in these MS3D-panels, to have full control, what will be stored in output file. that gives you the chance to tweak the output to your purpose and have all the features of ms3d, that blender does not has or handle in an other way.
for the full list of implemented features, please visit the wiki page