Does Facebook chat work for test users?

I have a project where part of the work is doing usability testing for an alternate interface to Facebook and this requires using the chat functionality for a specific test. I have created some test users and made them friends with each other. I am now testing by just logging in as two test users on Facebook.com on two separate browsers (Firefox 7 and Chrome 14.0.835.186) on the same machin开发者_开发问答e. Everything seems to work OK, but both of the users' chat windows indicate that no one is available to chat.

Is there some sort of permission I need to give to the test users when I create them for chat to work correctly? Or is there something that prevents this from happening (special for test users? being on the same machine?)

Any help would be appreciated.

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It's a confirmed and assigned bug. See https://developers.facebook.com/bugs/317432454946419/