I have a script from EBS 11 that returned the sid and username for forms sessions that were blocking

I have a script from EBS 11 that returned the sid and username for forms sessions that were blocking themselves and other.  After the upgrade to R12 it the username is no longer valid.  What tables should I add to the query to find a username?

Here is the 11.5.7 code that was working:

       SELECT DISTINCT a.sid
            , a.id1  bboy
            , vs.username
            , vs.machine
            , vs.event
            , vs.action
            , vs.status
            , vs.module
            , to_char(to_date(vs.seconds_in_wait,'sssss'), 'HH24:MI:SS') last_call
            , fu.user_name
            , fu.description
         FROM v$lock a
            , v$lock b
            , v$session vs