title: autoreply program sendmail giving "DSN: Service unavailable" error
body: <p>I am trying to use an auto reply program for one of the users.</p>
  
  <p>It works fine when I have user email address defined in <code>.forward</code> file but it gives following error when I put it in script:</p>
  
  <pre><code>Jun 28 12:25:38 localhost sendmail[5210]: s5SJPFkN005208: to="|/home/alpha/autoreply.pl", ctladdr=alpha@localhost (501/501), delay=00:00:10, xdelay=00:00:00, mailer=prog, pri=60446, dsn=5.0.0, stat=Service unavailable
  Jun 28 12:25:38 localhost sendmail[5210]: s5SJPFkN005208: s5SJPckN005210: DSN: Service unavailable
  </code></pre>
  
  <p>Do I have have make any changes in sendmail configs (i.e. symbolic link etc)?</p>
  
  <p>Thanks.</p>