It is good to note here that DBCC INPUTBUFFER requires the user executing to
be member of the sysadmin fixed server role. One way to handle this is to
specify user or login with sufficient privileges in EXEC (you can use EXEC
AS LOGIN or USER:

INSERT INTO SQLLog (language_event, parameters, event_info)
EXEC('DBCC INPUTBUFFER(@@SPID);') AS LOGIN = 'admin_login';

HTH,

Plamen Ratchev
http://www.SQLStudio.com