DOCBOOK: pdf file bookmark control

Hello, I'm making pdf file from sgml using openjade, docbook dtd 3.1 &
pdftex on my redhat linux box.

A pdf file is well made with the bookmark shown, but I don't want the
bookmark to be shown. How can I hide the bookmark? Which tex file should I
modify or Can I give a option to pdftex?

thanks

cjw