How to do a no follow on site search

[Apptixweb]

We have a site search that is causing a huge amount of errors as the SEOmoz crawler is showing these as duplicate content. Our first thought was to do a no-follow on the site-search directory, but we realized that the site search is /site-search.aspx and URl strings appear at the end for hundreds of pages.

How dow we/how can we no-follow an undetermined amount of URL strings?

[AlanMosley]

Are you sure you want to no follow, i would think that no index would be better, let them follow so that links can be found and link juice flow.

in robots.txt add
disallow/ site-search

[Apptixweb]

Thanks for the tip Alan!

SEOmoz is showing errors for all of these as it is causing duplicate content. We just launched a new site with a CMS and the search is a bit different than our old site. The site search has also inflated our site from roughly 400 pages to over 2500 in SEOmoz.