Update images embedded in posts

I have a blog which has been redesigned a few times and I have image thumbnails in a whole mess of sizes. I used the plugin Force Regenerate Thumbnails (which is awesome by the way) to resize all the thumbnails to my current specs and delete all the old sizes. The problem is there are literally hundreds of old posts now who’s images don’t show up because the img src no longer matches with the filename for example,

http://website.com/wp-content/uploads/2009/01/image-150×150.jpg

might now called

http://website.com/wp-content/uploads/2009/01/image-190×190.jpg

If all my images were the same dimensions I could just do a find replace in the database, but unfortunately they’re all different sizes. Is there a plugin or clever hack I could use to have wordpress automatically update old embeds with the new thumbnail sizes?