title: x-mailer header, phpmailer and spam filters
body: <p>I am a newsletter plugin developer for WordPress (Knews). It uses phpmailer to send.</p>
  
  <p>One user has contacted with me about an issue: all his emails (sent through phpmailer) goes to spam.</p>
  
  <p>He has solved adding a header param:</p>
  
  <p>$mail->XMailer...</p>
  
  <p>Phpmailer uses a default x-mailer param (phpmailer) if you doesn't set it, is this value bad for spam filters? What was the better value?</p>
  
  <p>Thanks,
  Carles Reverter.</p>