May superagent be causing this issue?
Here's some probably related piece: https://github.com/visionmedia/superagent/blob/13ff9b3a1bec34020c7d5dfcf88bbb26d67b9ee1/lib/node/index.js#L150
I mention this cause I'm working with Gerardo on the same project, and know for a fact that library is being used, plus ran some tests that indicate the problem might be there...