When the option sitepackages is set to true, the package can't be imported from the tests directory. I can only imagine two reasons for this: either the virtualenv is not activated at all or the package is not installed inside the virtualenv. Here is a minimal example which demonstrates the issue: http://bpaste.net/show/Vl95x5RftJQo4RZ91Sam/. If you set the option sitepackages to false, the tests can be run and pass.
Issue #80 on hold