<?php
$host="mxs.mail.ru";
$port="25";
$from="errou@mail.ru";
$to="errou@mail.ru";
$text="test";

$f=fsockopen($host,$port);
  fputs($f, "HELO {$_SERVER['SERVER_NAME']}\r\n"); 
  fputs($f,"MAIL FROM: <$from>");
print(fgets($f));
print(fgets($f));
  fputs($f,"RCPT TO: <$to>");
  fputs($f,"DATA");
  fputs($f,"$text");
  fputs($f,"RSET");
  fputs($f,"QUIT");
?>