PHP的一个完整SMTP类(解决邮件服务器需要验证时的问题)

smtp.php
class smtp
{
/* Public Variables */
var $smtp_port;
var $time_out;
var $host_name;
var $log_file;
var $relay_host;
var $debug;
var $auth;
var $user;
var $pass;
/* Private Variables */
var $sock;
/* Constractor */
function smtp($relay_host = "", $smtp_port = 25,$auth = false,$user,$pass)
{
$this->debug = FALSE;
$this->smtp_port = $smtp_port;
$this->relay_host = $relay_host;
$this->time_out = 30; //is used in fsockopen()
#
$this->auth = $auth;//auth
$this->user = $user;
$this->pass = $pass;
#
$this->host_name = "localhost"; //is used in HELO command
$this->log_file = "";
 
$this->sock = FALSE;
}
/* Main Function */
function sendmail($to, $from, $subject = "", $body = "", $mailtype, $cc = "", $bcc = "", $additional_headers = "")
{
$mail_from = $this->get_address($this->strip_comment($from));
$body = ereg_replace("(^|( ))(.)", "1.3", $body);
$header .= "MIME-Version:1.0 ";
if($mailtype=="HTML"){
$header .= "Content-Type:text/html ";
}
$header .= "To: ".$to." ";
if ($cc != "") {
$header .= "Cc: ".$cc." ";
}
$header .= "From: $from<".$from."> ";
$header .= "Subject: ".$subject." ";
$header .= $additional_headers;
$header .= "Date: ".date("r")." ";
$header .= "X-Mailer:By Redhat (PHP/".phpversion().") ";
list($msec, $sec) = explode(" ", microtime());
$header .= "Message-ID: <".date("YmdHis", $sec).".".($msec*1000000).".".$mail_from."> ";
$TO = explode(",", $this->strip_comment($to));
if ($cc != "") {
$TO = array_merge($TO, explode(",", $this->strip_comment($cc)));
}
if ($bcc != "") {
$TO = array_merge($TO, explode(",", $this->strip_comment($bcc)));
}
$sent = TRUE;
foreach ($TO as $rcpt_to) {