I like how Oracle educates developers about the proper handling of DTD's. (They didn't break it by accident for the third time already, right? RIGHT?!)
Of course not.
Oracle would never do anything bad to a developer community.
To be honest though, if this have already happened TWICE do people really have any excuse for using a server that goes down a lot for something important?
Why would you NOT just download the stuff on some separate server and at most run some cronjob to keep it up to date?
See the link to the w3c - several times they've started delivering 503 HTTP error codes, hoping that the applications would start to break. It didn't have a big effect, either because the application didn't actually use the DTD they've retrieved for anything or because they broke in a non-obvious manner (like with the servers I'm administering). Had the outage been shorter or if I wasn't monitoring the Tomcat JVMs it could've stayed under the radar. That's one of the reasons I've made this submission.