A filter to automatically link email addresses in a spam-safe manner

PHP WP: auto email filter.php

<?php
function driv_auto_email($text) {
  $matches = array();

	if (preg_match('/[A-Za-z\.\-\_]*@[A-Za-z\-\_]*\.[A-Za-z\.]*/', $text, $matches)) {
		foreach ($matches as $match) {

			$email = '';
			$chars = array();
			for ($i=0, $len = strlen($match); $i < $len; $i++) { 
				$chars[] = ord($match[$i]);
			}
			$script = "var t = [" . implode(', ', $chars) . "]; var email = '&#' + t.join(';&#') + ';'; document.write('<a href=\"mailto:' + email + '\">' + email + '</a>');";
			$tag = '<script type="text/javascript">%s</script>';
			$text = str_replace($match, sprintf($tag, $script), $text);

		}
	}
	return $text;
}