Formatting.php is broken :(

Link: https://www.alfaj0r.com/library/christopher-hitchens/god-is-not-great-how-religion-poisons-everything/
I keep getting the error “Warning: preg_replace() [function.preg-replace]: No ending delimiter ‘:’ found in /home/.newley/alfajor/alfaj0r.com/blog/wp-includes/formatting.php on line 668”

Here’s a copy of my file: https://www.alfaj0r.com/misc/formatting.txt

I suspect the problem came with the plugin “More Smilies“, which is no longer supported. I think I had to modify some files when I installed it, but it was a long time ago, and I really didn’t have any idea of what I was doing ??

I’ve tried replacing the formatting.php file with another one, from the default install of WP, but the errors propagate to other files that call functions on formatting.php, so… I don’t know what to do. And that’s why I’m here ??