Hi The recently added new function allowing administrators to impersonate other users is a really useful tool - thank you very much. It works great on our development server. Unfortunately, it does not work on our production server which relies on external authentication via Apache. Is this a common problem? See below for the output in the logs, when I tried to switch from 'hansrudolf.hotz@fmi.ch' to 'Tim.Roloff@fmi.ch'. Has anybody else activated this functionality (with or without success)? Regards, Hans 172.27.28.201 - - [23/Jan/2012:13:25:11 +0200] "POST /admin/impersonate HTTP/1.1" 200 - "http://galaxy.fmi.ch/admin/impersonate?webapp=galaxy" "Mozilla/5.0 (X11; U; Linux i686; en-US) AppleWebKit/533.4 (KHTML, like Gecko) Chrome/5.0.375.86 Safari/533.4" galaxy.web.framework WARNING 2012-01-23 13:25:23,526 User logged in as 'hansrudolf.hotz@fmi.ch' externally, but has a cookie as 'Tim.Roloff@fmi.ch' invalidating session 172.27.28.201 - - [23/Jan/2012:13:25:23 +0200] "GET /root HTTP/1.1" 200 - "http://galaxy.fmi.ch/admin/impersonate" "Mozilla/5.0 (X11; U; Linux i686; en-US) AppleWebKit/533.4 (KHTML, like Gecko) Chrome/5.0.375.86 Safari/533.4"