Lucky...
I just found the solution at this address http://www.adobe.com/support/techdocs/66ca.htm

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>Ref.: Adobe Acrobat 4.0
>
>Acrobat PDFWriter popup automaticaly a dialog box to gather information on the PDF file to be saved... just before transforming/saving any report in a PDF format on disk.
>
>Anyone knows how to get any control on this box?
>
>Thanks in advance.