Have you tried installing Gnomad using urpmi? That's Mandriva's package manager, and it should help you to resolve your dependancies. You'll need to search for a guide to using it (in these forums for example) and you'll also need to add a few repositories so that it can find the right packages for you and install them.

I checked out a mirror site and Gnomad is a contributed package. For example on here: ftp://anorien.csc.warwick.ac.uk/Mand.../media/contrib

Provided your version of urpmi is clean and stable that should help you. If you decide to try this, add repositories in the /main /contrib /jpackage and /official/updates/2006.0/main_updates/ directories.

Once you've mastered package management you've achieved a lot. Most people recommend easy urpmi to help you set things up http://easyurpmi.zarb.org ... but it can be a little misleading for some users IMHO as there's no guarantee that repositories listed there remain current.