tvunget download dialog-boks i mac

Jeg har efter en god tids søgning fundet flg. kode, som giver en tvunget 'save As'-dialogbox, når brugeren klikker på linket. Det virker i IE til pc, men ikke til Mac. Hvorfor? og hvordan får jeg det til at virke der også?

HTML-filen
<html>
<head>
</head>
<body>
File download:
<A HREF="startDownload.asp?File='absolutefilepath'&Name='filenameandext'Size='filesize'" onMouseOver="self.status='detaljert.jpg'; return true;" onMouseOut="self.status=''; return true;">detaljert.jpg</A>
</body>
</html>

ASP-scriptet:
<%
Response.Buffer = True
Dim strFilePath, strFileSize, strFileName

Const adTypeBinary = 1

strFilePath = Request.QueryString("File")
strFileSize = Request.QueryString("Size")
strFileName = Request.QueryString("Name")

Response.Clear

'8*******************************8
' Requires MDAC 2.5 to be stable
' I recommend MDAC 2.6 or 2.7
'8*******************************8
Set objStream = Server.CreateObject("ADODB.Stream")
objStream.Open
objStream.Type = adTypeBinary
objStream.LoadFromFile strFilePath

strFileType = lcase(Right(strFileName, 4))
   
    ' Feel Free to Add Your Own Content-Types Here
    Select Case strFileType
        Case ".asf"
            ContentType = "video/x-ms-asf"
        Case ".avi"
            ContentType = "video/avi"
        Case ".doc"
            ContentType = "application/msword"
        Case ".zip"
            ContentType = "application/zip"
        Case ".xls"
            ContentType = "application/vnd.ms-excel"
        Case ".gif"
            ContentType = "image/gif"
        Case ".jpg", "jpeg"
            ContentType = "image/jpeg"
        Case ".wav"
            ContentType = "audio/wav"
        Case ".mp3"
            ContentType = "audio/mpeg3"
        Case ".mpg", "mpeg"
            ContentType = "video/mpeg"
        Case ".rtf"
            ContentType = "application/rtf"
        Case ".htm", "html"
            ContentType = "text/html"
        Case ".asp"
            ContentType = "text/asp"
        Case Else
            'Handle All Other Files
            ContentType = "application/octet-stream"
    End Select
   
   
    Response.AddHeader "Content-Disposition", "attachment; filename=000" & strFileName
    Response.AddHeader "Content-Length", strFileSize
    ' In a Perfect World, Your Client would also have UTF-8 as the default
    ' In Their Browser
    Response.Charset = "UTF-8"
    Response.ContentType = ContentType
    Response.BinaryWrite objStream.Read
    Response.Flush

objStream.Close
Set objStream = Nothing
%>