[galaxy-dev] External User Authenticaion

Hi all - I'm trying to use external user authentication with Galaxy. The external authentication passes to Galaxy the username with the mail domain at HTTP_USER. In galaxy.ini, I enable: use_remote_user = True When I try to access Galaxy, I get the message: Galaxy is configured to authenticate users via an external method (such as HTTP authentication in Apache), but a username was not provided by the upstream (proxy) server. This is generally due to a misconfiguration in the upstream server. But nothing in paster.log indicating what the error is. How do I track this down?