+1  A: 

You can write

INSERT INTO REF_USER_ROLE_XRE
  SELECT Param1, Param2, Param1, 
    (select to_char(sysdate, 'DD-MON-YY') from  dual)
FROM 
    (SELECT ? AS Param1, ? AS Param2) params
mdma
Exactly what I was looking for. Thanks a lot.
Chris Lieb