gp.recipe.node still failing on missing bin directory

[iivvoo]

Most likely this is issue #18 all over again. The following trivial buildout

[buildout]
parts =
    jstests

[jstests]
recipe = gp.recipe.node
npms = 
    karma

Fails when trying to listdir on parts/jstest/bin:

While:
  Installing jstests.

An internal error occurred due to a bug in either zc.buildout or in a
recipe being used:
Traceback (most recent call last):
  File "/home/ivo/tmp/node-bo/local/lib/python2.7/site-packages/zc/buildout/buildout.py", line 1942, in main
    getattr(buildout, command)(args)
  File "/home/ivo/tmp/node-bo/local/lib/python2.7/site-packages/zc/buildout/buildout.py", line 622, in install
    installed_files = self[part]._call(recipe.install)
  File "/home/ivo/tmp/node-bo/local/lib/python2.7/site-packages/zc/buildout/buildout.py", line 1366, in _call
    return f()
  File "/home/ivo/tmp/node-bo/eggs/gp.recipe.node-0.10.26.0-py2.7.egg/gp/recipe/node/__init__.py", line 134, in install
    scripts = os.listdir(os.path.join(node_dir, 'bin'))
OSError: [Errno 2] No such file or directory: '/home/ivo/tmp/node-bo/parts/jstests/bin'

Creating this bin dir and rerunning buildout will make it succeed but it won't actually install anything in it. Nor will it install (in this case) 'karma' in the buildout bin dir (for which I will file a separate issue)