Recently on Ubercart.org the contrib links where changed from
This broke all existing links to contrib modules posted on the net and on this website. This needs to be resolved as it's made the forums very useless.
I would recommend this solution.
Install the path redirect module. Write a script to populate the path_redirect table with 301 redirects for all the old modules. The old URL names were simply contrib/[nid] so this should be fairly easy to do.