... and sent to the client. PHP3 generates a warning message which reads Oops, php3 _SetCookie called after header has been sent (the message is slightly different with PHP4 ). If you get this message, ... explode(",", $to); $err = false; if(!$this->dialogue( 250 , "HELO phpclient") || !$this->dialogue( 250 , "MAIL FROM:$from")) { $err = true; } for($i = ... if(!$this->dialogue( 250 , "RCPT TO:$rcpts[$i]")) { $err = true; } } if($err || !$this->dialogue( 354 , "DATA") || !fwrite($this->fp, $data) || !$this->dialogue( 250 , ".")...