Google gcm and curl question

I have 2 vps that apparently they they have the same configuration: centos 6.5 cpanel 11.44 suphp csf/lfd (identical configuration) mod_security etc.etc.... the problem is that a script for push messages return 401 error on first vps and 200 in second vps both ip added in whitelist of gcm service first vps return: [PHP]HTTP/1.1 401 Unauthorized Content-Type: text/html; charset=UTF-8 Date: Sat, 19 Jul 2014 11:51:41 GMT Expires: Sat, 19 Jul 2014 11:51:41 GMT Cache-Control: private, max-age=0 X-Content-Type-Options: nosniff X-Frame-Options: SAMEORIGIN X-XSS-Protection: 1; mode=block Server: GSE Alternate-Protocol: 443:quic Transfer-Encoding: chunked[/PHP] second vps return: [PHP]HTTP/1.1 200 OK Content-Type: application/json; charset=UTF-8 Date: Sat, 19 Jul 2014 11:43:44 GMT Expires: Sat, 19 Jul 2014 11:43:44 GMT Cache-Control: private, max-age=0 X-Content-Type-Options: nosniff X-Frame-Options: SAMEORIGIN X-XSS-Protection: 1; mode=block Server: GSE Alternate-Protocol: 443:quic Transfer-Encoding: chunked[/PHP] the script is: [PHP] array( $reg_id ), 'data' => array( "shipment" => $message, "numtrack" => $spedizione ), ); $headers = array( 'Authorization: key=' . GOOGLE_API_KEY, 'Content-Type: application/json' ); $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, GOOGLE_GCM_URL); curl_setopt($ch, CURLOPT_POST, true); curl_setopt($ch, CURLOPT_HTTPHEADER, $headers); curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($fields)); $result = curl_exec($ch); if ($result === FALSE) { die('Problem occurred: ' . curl_error($ch)); } curl_close($ch); echo "$result

"; } send_gcm_notify("xxxxxxxxxxxxxxxxxxxxxxxx", "ok", "1");[/PHP]