I'm using this Class

<?php
class paypalIPN {
    //sandbox:
    private $paypal_url = 'https://www.sandbox.paypal.com/cgi-bin/webscr';
    //live site:
    //private $paypal_url = 'https://www.paypal.com/cgi-bin/webscr';
    private $data = null;

    public function __construct()
    {
        $this->data = new stdClass;
    }

    public function isa_dispute()
    {
        //is it some sort of dispute.
        return $this->data->txn_type == "new_case";
    }

    public function validate()
    {
        // parse the paypal URL
        $response = "";
        $url_parsed = parse_url($this->paypal_url); 
        // generate the post string from the _POST vars aswell as load the
        // _POST vars into an arry so we can play with them from the calling
        // script.
        $post_string    = '';    
        foreach ($_POST as $field=>$value) {        
            $this->data->$field = $value;
            $post_string .= $field.'='.urlencode(stripslashes($value)).'&'; 
        }
        $post_string.="cmd=_notify-validate"; // append ipn command

        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $this->paypal_url);
        //curl_setopt($ch, CURLOPT_VERBOSE, 1);
        //keep the peer and server verification on, recommended 
        //(can switch off if getting errors, turn to false)
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $post_string); 
        $response = curl_exec($ch);

        if (curl_errno($ch))
        {
            die("Curl Error: " . curl_errno($ch) . ": " . curl_error($ch));
        } 
        curl_close($ch);
        return $response;
        if (preg_match("/VERIFIED/", $response))
        {  
            // Valid IPN transaction.
           return $this->data;
        }
        else
        {  
            return false;         
        }
    }
}

ANd i recall in this mode:

 public function get_ipn()
{
    $ipn = new paypalIPN();
    $result = $ipn->validate();
    $logger = new Log('/error.log');
    $logger->write(print_r($result));
}

But I obtain only "VERIFIED" or "1" (whitout or with the print_r function).

I just tried also to return directly the raw curl response with

return $response;

or

return $this->response;

or also

return $this->parse_string;

but everytime I receive only "1" or "VERIFIED".......

Thank you very much