[rhn-users] logwatch : sendmail warning

[FM]

server : RHEL 3

All servers send their logwatch to my mail server.

Each logwatch have this entry :

  --------------------- sendmail Begin ------------------------


**Unmatched Entries**
    STARTTLS=client, relay=mail.domaine.com, version=TLSv1/SSLv3, 
verify=FAIL, cipher=AES256-SHA, bits=256/256: 1 Time(s)

  ---------------------- sendmail End -------------------------


All mail arrived but I'm trying to removing this warning / error.

Do I just have to get to my "sendmail servers" the SMTP cert of my real 
mail server ?

Thanks