Elias,
I too have 'thousands' of duplicated errors in SEOmoz. Most of which are because it is returning
/abc.com as a different page to /ABC.com
Surely Google doesn't do that? Just because one URL is in capital and the other small case? I also have no idea where SEOmoz is picking that up from......possibly links internal to the page with the hyperlink using different case?
It seems to me this is too sensitive and for me to fix that would take WEEKS!!!! I fail to see if there would be any uplift if Google sees beyond that issue as its cosmetic and not functional.
Regards
Andy