Code is Being Dropped!

I like WP-Codebox.

If I enter code between “<pre lang=”rsplus”> and “, and then publish the page or post, I get the expected the results….at first.

However, as soon as I edit the post or page and then publish, I see that large chunks of code are being wiped out or dropped. I am then forced to update all the code blocks again. Clearly, this is not viable for long pages or continued use.

Why is this happening? What can I do to stop this?

http://wordpress.org/plugins/wp-codebox/