PHP vs ASP headers

Why does this code in ASP Response.addheader "Content-type","application/pdf" Response.addheader "Content-Disposition","inline; filename=25-1.pdf" Result in these headers HTTP/1.1 200 OK Server: Microsoft-IIS/5.0 Date: Thu, 07 Nov 2002 19:57:52 GMT Content-type: application/pdf Content-Disposition: inline; filename=25-1.pdf Content-Type: text/html Cache-control: private Transfer-Encoding: chunked When this code in PHP 4.2.3 Isapi header("Content-type: application/pdf"); header("Content-Disposition: inline; filename=25-1.pdf"); header("Content-Type: text/html",false); header("Cache-control: private"); header("Transfer-Encoding: chunked"); Result in these headers (Note the Connection: Close) HTTP/1.1 200 OK Server: Microsoft-IIS/5.0 Date: Thu, 07 Nov 2002 19:59:50 GMT Connection: close Content-type: application/pdf Content-Disposition: inline; filename=25-1.pdf Content-Type: text/html Cache-control: private Transfer-Encoding: chunked I need to stop IIS from sending the Connection: Close Charles Killmer