[eluser]Ajaxboy[/eluser]
Because it is on a Windows 2003 server, I am not sure if this would qualify as bug.
The section that handles this area is in cjax/cjax.php, I would not able to reproduce because I don't have access to a Window 2003 server, and don't know the type of configuration in your installation.
As I mentioned before, Windows 2003 has been dumped by PHP. With some debugging you should be able to fix it though.