http proxy authentication is not working if one uses a org.codehaus.xfire.client.Client. Username and password were provided as stated in the documentation, but they never arrive in the http message. According to bug XFIRE-809, this should be fixed since 1.2.4, but it still does not work in 1.2.5. (I cannot reopen XFire-809) After some debugging I found CommonsHttpMessageSender to be the culprit. In the createClient() method, it sets the proxy credentials as part of the client state. In the open() method - right after calling createClient() - it creates a new HttpState, overwriting the original client state that contained the proxy credentials. To fix this, I moved the initialization of the proxy credentials from createClient() to open(), right where the http credentials are set. This setup works fine for me.