Find emailaddresses, make clickable and encode with base64

gistfile1.aw

/********Code based on https://gist.github.com/907604 *********

The code find email addresses and proteceds for bots.
Make the addresses clickable with webtoolkit.base64.js and the following code (JQuery requiered):
	$('a').each(function() {
		var href, mailaddress;
		href = $(this).attr('href');

		if(href.search(/mailto:/) != -1)
		{
			mailaddress = href.substr(6);
			mailaddress	= Base64.decode(mailaddress);
			$(this).attr('href', 'mailto:'+mailaddress);
			
			if($(this).html().search(/ät|at/) != -1)
			{
				$(this).html(mailaddress);
			}
		}
	});
********************************************************************/


function make_email_clickable($html) {
$regexp = '/
    				( # leading text
       					<\w+.?>| # leading HTML tag, or
    					[^=:!\'"\/]| # leading punctuation, or
    					<a.?href="mailto:|
    					^ # beginning of line
    				)
					(
						[a-z]+[a-z0-9\-\.\_]+?@[a-z0-9\-\.]+[a-z]{2,6}
					)
    				(
    					[[:punct:]]||\s|<|$
    				) # trailing text
    			/x';
    	
    	return preg_replace_callback($regexp, function($matched) {
    		list($all, $before, $address, $after) = $matched;
    	
    		// already linked
    		if (preg_match('/<a\s/i', $before)) {
    			return preg_replace_callback("/[a-z]+[a-z0-9\-\.\_]+?@[a-z0-9\-\.]+[a-z]{2,6}/x", function($matches){return base64_encode($matches[0]);}, $all);
    		}
    	
    		$text 		= strtr($address,array("@"=> " ät "));
    		$address	= base64_encode($address); 
    	
    		return $before.'<a href="mailto:'.$address.'">'.$text.'</a>'.$after;
    	}, $html);
}

echo make_email_clickable("daslampe@lano-crew.org");