How can I Search/Replace problem URLs?

I imported a large site with a couple thousand posts from Movable Type, then updated the URLs to use hyphens. Several dozen URLs have now got instances where there are multiple hyphens.

e.g.

http://www.myblog.com/2011/07/review-pt-1—council-on-terms-of-reference/

I’d like to do a search/replace of all URLs in my WP blog to turn “—” into “-“. Seems simple enough but I cannot find a search query for PHPMyAdmin that would do this without affecting other data.

Any advice would be greatly appreciates on how to accomplish a “quick fix”.

Thanks!