Up-to-date addon (Blender ≥ 2.7.2 supported!) for working with Quake 3 model format, written from scratch.
Can deal with animation (via the Shape Keys), textures and md3 tags (added as Empty objects).
More info on BlenderWiki.
Used this format reference.
2.6.9 very likely will work, though it becomes increasingly complex to test & maintain python 3.3 builds due to lack of features present in newer versions of python and significant API mismatches in bunch of supporting software.