PEAR :: Manual: Mail_RFC822. Eureka, I discovered that I had just forgotten the declaration that asks for the right file that is require_once 'Mail.php' That's is. Then you can use the method Mail::parserecipients("strong") to get the list. Wow, amazing how i figured this out just when I went to bed. The problem is that code fragment documented here, doesn't have the require_once piece since it is so obvious to PEAR programmers.