[Cooker] Why is linux-mandarke an open smtp server?

[Bill Shirley]

Out: 554 Service unavailable; [212.43.244.20] blocked using
inputs.orbz.org
 In:  DATA
 Out: 503 Error: need RCPT command
 In:  RSET
 Out: 250 Ok
 In:  QUIT
 Out: 221 Bye

Just curious,
Bill