Hallo,
folgendes habe ich probiert
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_POST, true);
$data = array(
'foo' => 'foo foo foo',
'bar' => 'bar bar bar',
'baz' => 'baz baz baz'
);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data)
$output = curl_exec($ch);
curl_close($ch);