It looks like the version of virtualenv needs updating – the current one is unable to build Python 3.4 virtualenvs:

[workspace] $ /usr/bin/python3 /var/lib/jenkins/shiningpanda/jobs/32a3c596/virtualenv.py --distribute /var/lib/jenkins/shiningpanda/jobs/32a3c596/virtualenvs/d41d8cd9
Failed to import the site module
Traceback (most recent call last):
File "/var/lib/jenkins/shiningpanda/jobs/32a3c596/virtualenvs/d41d8cd9/lib/python3.4/site.py", line 67, in <module>
import os
File "/var/lib/jenkins/shiningpanda/jobs/32a3c596/virtualenvs/d41d8cd9/lib/python3.4/os.py", line 634, in <module>
from _collections_abc import MutableMapping
ImportError: No module named '_collections_abc'

collections-abc is one of the few API changes that happened between 3.3 and 3.4.

The fix should be very simple: upgrade to the latest version of virtualenv. It should be fully backwards compatible.