title: Set email headers so bounced emails go to a specific address
body: <p>From our rails app we send out some system-generated emails with the 'from' address set to noreply@ourdomain.com.  If these bounce they get sent back to this address by our mail server.  However, what i'd like to do is to not have bounced emails get sent back to noreply@ourdomain.com but to a different address, such as bounced@ourdomain.com.</p>
  
  <p>Is there a header or something i can set in the email that will achieve this, without me having to go and investigate the vagaries of our email server?  We send the mails out using exim in case that's relevant.</p>
  
  <p>cheers, max  </p>