$strCookie = 'PHPSESSID=' . $_COOKIE['PHPSESSID'] . '; path=/';
session_write_close();

$request = array(
	//CURLOPT_HTTPHEADER => array('Content-type: application/x-www-form-urlencoded'), 
    //CURLOPT_POST => false, 
	CURLOPT_USERAGENT => 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.52 Safari/537.17', 
	CURLOPT_AUTOREFERER => true, 
	CURLOPT_FOLLOWLOCATION => true, 
	CURLOPT_SSL_VERIFYPEER => false, 
    CURLOPT_POSTFIELDS => http_build_query($params), 
	CURLOPT_COOKIE => $strCookie, 
    CURLOPT_RETURNTRANSFER => false //Important!
);

http://www.smooka.com/blog/2009/07/24/maintaining-php-session-when-using-curl/