Replace Content in PRE Tags with HTML Entities

If you have a website that relies heavily on PRE tags, you know the important of converting PRE tag content to their HTML entities. Doing so prevents worlds of possible rendering issues. The following PHP snippet HTML-Entitizes (?) any code within PRE tags:

//replaces pre content with html entities
function pre_entities($matches) {
 return str_replace($matches[1],htmlentities($matches[1]),$matches[0]);
}
//to html entities;  assume content is in the "content" variable
$content = preg_replace_callback('/<pre.*?>(.*?)<\/pre>/imsu',pre_entities, $content);

I use this for just about every post I write. You could also stick this in your CMS if you have clients that may have use for PRE tags.