apache - server doesn't respond on POST Request with CURL + PHP -

i have simple php script, uses curl send http post request remote server.

$ch = curl_init(); curl_setopt($ch, curlopt_url, 'http://91.250.77.10/test.php'); curl_setopt($ch, curlopt_post, 1); curl_setopt($ch, curlopt_postfields, array('a' => 'b')); curl_setopt($ch, curlopt_returntransfer, 1); $contents = curl_exec($ch); $error = curl_error($ch); curl_close($ch); if ($error)      echo $error; else     echo $contents; 

this results in error: "no response server". request can't found in access log of remote server, too!

what's more, if send postfields querystring, i.e.:

curl_setopt($ch, curlopt_postfields, '&a=b'); 

then fine.

it seems wrong apache or php configuration on remote server. hints?

edit:

as now, looks server doesn't accept (or correctly handle) requests content-type: multipart/form-data (curl uses type when setting array postfields, not when setting string.)

since need send file request, have use multipart/form-data. how server correctly handle this?

if pass array curlopt_postfields form submitted multipart/form-data there possibility remote end not accepting encoding type.