Here is an example I typed up from an OBJ batch import script. Add this into your Text Editor and hit Run Script.
It works perfect with 2.69.
import os
import bpy
# path_to_3ds should be the folder where all your sub directories are for your 3ds files
# main_dir is the folder where the sub directory folders that actually contain your 3ds files are.
# sub_dir is the actual folder that contains all the 3ds files.
# Example: path_to_3ds = os.path.join('C:\\users\joe\desktop\Main Folder', 'Folder 1')
# Make sure your Main_dir has "C:\\" this needs two "\" or it wont work.
# if you have divided all your files into seperate sub directories, you will need to import each folder seperately.
# Ex: C:\\users\joe\desktop\Main Folder', 'Folder 1') - Import then,
# C:\\users\joe\desktop\Main Folder', 'Folder 2') - Import then,
# C:\\users\joe\desktop\Main Folder', 'Folder 3') and so on...
path_to_3ds = os.path.join('main_dir', 'sub_dir')
file_list = sorted(os.listdir(path_to_3ds))
autodesk_list = [item for item in file_list if item.endswith('.3ds')]
for item in autodesk_list:
path_to_files = os.path.join(path_to_3ds, item)
bpy.ops.import_scene.autodesk_3ds(filepath = path_to_files)
Hope this helps :^)