Problem with Internet Explorer when downloading / viewing dynamically generated PDF files

Hello list-members I have written a script which dynamically generates PDF documents (with PDFlib). The link to the PDF file is presented as a static link (thanks btw to Richard Lynch and his previous contributions to this list on the subject "force download"). It is redirected to the script via a htaccess file. If the name of the PDF document matches a certain pattern, than the script will output the document, if not, a 404 error page will pop up. Everything works very well with all kinds of browsers, except Microsoft Explorer (tested with Windows Explorer 6 SP1, Internet Explorer 5.2 for Macintosh). And I want to know why. Explorer shows the PDF document as plain text only. Trying to save the linked document to the computer (right click) gives something like "The server can not be reached or the document does not exist." I know that explorer is a real p.i.t.a. when it comes to all kinds of web standards. And my best guess is that this could have to do with headers, or? Google was not my friend this time, I might say. /frank