Reader: First off, great site. I've finally found some info on the problem I keep hearing about from my readers. And your validator actually shows me an error, instead of incorrectly validating. If I can trouble you for a minute of your time, can you check out my feed? I don't know how to fix it. It works fine in FeedReader, but is blowing up elsewhere. Any tips are a big help.
Randy: Gotta love positive feedback like this. The problem was a space in the HTTP header-name. Another problem that isn't addressed by the other feed validators. Similar to the Wordpress problem.