When writing a post about a new WordPress plugin I've developed (a Xanga/Wordpress crossposter), I ran into the weirdest error I have ever met in my experience with computers. I have no clue what causes it, so I'm posting here for ideas.
When I clicked "Save as Draft" after finishing the entry, my server did not save it, but instead returned an error 500 -- Internal Server Error. This is a regularly seen message in Perl coding, but not in PHP. Since I had just uploaded a slight code change to my plugin, I thought that was the cause, thinking I had just made a typo in my code. It turns out it isn't quite so simple. I couldn't find any typos, so I completely disabled my plugin and the error still occurred.
On a hunch, I tried removing all but a little bit of my entry text, and it worked! I then added the whole entry back in, bit by bit, until I found the offending part. It turns out that the two-word phrase "Perl for" crashes WordPress. It doesn't matter if it is in the post title or body, what the context is, or whether it is capitalized. I know that the problem is in WordPress itself (at least my installation), because the problem occurs with all plugins deactivated.
Does anybody have any idea why WordPress is allergic to the phrase "perl for"?
FYI, I am using WordPress 1.2.