Using a local install of phantomjs for "ember test"

From a continuous integration perspective, I would prefer to use a local install instead of a global one as the docs currently state. I've searched for a while and looked at the api from "ember test --help" and I don't see the ability to explicitly state the location of phantomjs - ember expects it to be available globally.

Is it possible to run something like "ember test --phantomjs node_modules\phantomjs\bin\phantomjs"? Or modify testem.js to state phantomjs location?