Verified answer

I believe you could create a 301 redirect from each of the old addresses to it's new counterpart, that could require a tedious editing session and some .htaccess file code learning, a 301 redirect also shifts any page rank of the old url to the new one, it's an acceptable solution with the search engines.

Hopefully you went from a cryptic post-1213 url format to the page title in the url, which should pay off in seo terms in the long run.

If your site is registered with Google Webmaster tools you can make a reindex request that might speed the search listing updates.

You have to 301 redirect all old exiting url to new url