[Andreas]

File attachment.php, at the very end

Replace

PHP Code:

echo $attachmentinfo["$imagetype"]; 


With

PHP Code:

// UploadBandwithLimitHack
// Original line: echo $attachmentinfo["$imagetype"];
$bandwidth = 30; // Desired max. bandwidth in KB/s.
$i = 0;
while ($i < strlen($attachmentinfo["$imagetype"])) {
  echo substr($attachmentinfo["$imagetype"], $i, 1024);
  $i += 1024;
  flush();
  usleep(1000000/$bandwidth);
}
// UploadBandwidthLimitHack 


This might help, but isn't a good solution IMHO.