How to modify the BL UI startup?

I want to modify the located at Blender\2.72\scripts\startup\bl_ui so it can load some scripts of mine. I would like to add my script in this list “_modules” but I could not figure out how to do this.

Currently I have added the classic scriptstub (located at the script examples) and it works fine. However I would be interested to integrate it with the Blender’s mechanism.

# def load_custom():
#     import bpy
#     import os
#     name = ""
#     path = "C:\\mypath\\"
#     filepath = os.path.join(os.path.dirname(path), name)
#     global_namespace = {"__file__": filepath, "__name__": "__main__"}
#     with open(filepath, 'rb') as file:
#         exec(compile(, filepath, 'exec'), global_namespace)

# load_custom()

If you might wonder why I want to do this, I found that a good way to use the scripts while in development mode. This way I can keep my development file system intact (e.g. folder categories, git) while letting Blender load it on the fly.