shimmie2/contrib/emoticons/main.php

<?php
/**
 * Name: Emoticon Filter
 * Author: Shish <webmaster@shishnet.org>
 * License: GPLv2
 * Description: Turn :smile: into a link to smile.gif
 */

class Emoticons extends FormatterExtension {
	public function format($text) {
		$data_href = get_base_href();
		$text = preg_replace("/:([a-z]*?):/s", "<img src='$data_href/ext/emoticons/default/\\1.gif'>", $text);
		return $text;
	}

	public function strip($text) {
		return $text;
	}
}
add_event_listener(new Emoticons());
?>