It's the oddest thing. I'm writing a post on my blog, and I Save and Continue, and I get the error:
406: Not Acceptable
An appropriate representation of the requested resource /weblog/wp-admin/post.php could not be found on this server.
With a lot of trial and error, I figure out that I can't post so long as I have a 5th "from" in the text. It's a lot of text, this post, and , and there's 4 "from"s in it. But so long as that 5th one it there, I get that error. I can have all the rest of the post, and even add other words and it'll post---so long as there's 5th "from" in it, else I get that error.
Since "from" is a mySQL operations word, I looked for anything else out of the ordinary: semi-colons, parenthesis, etc., and took them out. Doesn't matter: still posts fine with 4 "from"s, errors
I ended up abbreviating it to "frm" and it'll post fine.