"Logged in As" someone else in 11i and R12

On the OAHOMEPAG "Logged in As" string, in the upper right corner of the page, indicates you are logged in as someone else.

If you are using F5 BigIP to off load SSL, then try not use the RAM cache in your HTTP profile or exclude some URI like /OA_HTML/AppsLogin, /OA_HTML/OA.jsp  in your cache setting for HTTP profile.