I have a 7-button Intellimouse explorer, and had to setup everything. I read through the arch wiki, and assuming that Mandriva uses xorg 7 or greater - you should be able to do the same.
http://wiki.archlinux.org/index.php/...e_scroll_wheel
Hope it works.
The only problem I have found is with the middle button. It doesn't want to close tabs in Firefox.