We're discussing it internally at the moment. A number of moderators have been running into the same problem lately. We're still trying to track down a consistent way to reproduce the problem, so if you can provide exact steps as to how you ran into it that would be helpful. After all, there are a number of ways to make a post
And it's been going on for a while I think. It does seem to be somewhat random. Perhaps related to the overall load on the servers? Background housekeeping activities?
Or maybe it's got some type of radar that's sensitive to someone getting ready to post a longer than average reply? Very annoying to have a five or six paragraph reply hang up and then disappear in a Site Unavailable message.
I've been paranoid enough to start posting a reply in a couple short posts instead of just 1 long post. And I try to remember to copy a long reply to the clipboard before I hit the submit button.
Any of you still receiving this error? There was a small ad that was causing issues in redirect when posting replies, but that has been resolved. If you are still experiencing this issue, we'll continue to dig.