ipdb autocompletion not working with locals and modules

Running a script as `python -m ipdb myscript.py` or 'ipdb myscript.py`, ipdb's tab auto completion will work with builtins, but not with locals and modules.

Launching ipdb from within the code with `import ipdb; ipdb.set_trace()` autocompletion works instead as expected.

To reproduce the error call a python script with -m ipdb (e.g. python -m ipdb myscript)), import a module (e.g. import numpy as np) and try to use autocomplete on the module (e.g. np.<TAB>). The expected behavior is to see the list of properties and functions of the module. Nothing happens instead.

lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04

apt-cache policy python-ipdb
python-ipdb:
  Installed: (none)
  Candidate: 0.8-1
  Version table:
     0.8-1 0
        500 http://archive.ubuntu.com/ubuntu/ trusty/universe amd64 Packages

python --version
Python 2.7.6