[TYPO3-english] RealUrl + Hooks

[Patrick Finkbeiner]

Hey Guys i'm trying to solve a problem which regards realurl and a self-written extbase extension.
I want to use the title of a product in the url which works perfectly except for some special characters like © and some html tags. (Product title is created with RTE).
So, i guess i have to use one of the given hooks,.. but how? 

With the following code snipped i can access my hook (what output of var_dump proves) but still get an exception.

realurl_conf.php:
$TYPO3_CONF_VARS['EXTCONF']['realurl'] = array (
	'encodeSpURL_postProc' => array(
		'productfinder' => 'EXT:productfinder/Classes/Hooks/RealUrlHook.php:user_Tx_Productfinder_Hooks_RealUrl->encodeSpURL_postProc'
	),
	'_DEFAULT' => array (
		'init' => array (
			'enableCHashCache' => 1,
			'enableUrlDecodeCache' => 1,
			'enableUrlEncodeHash' => 1,
…

Hook: RealUrlHook.php
/**
 * Hook for RealURL
 *
 * @package Hooks
 */
class user_Tx_Productfinder_Hooks_RealUrl extends tx_realurl {
	public function user_encodeSpURL_postProc(&$params, &$ref) {
		var_dump('test');
	}
}


…
Exception: 
t3lib_div::callUserFunction 
|No class named user_Tx_Productfinder_Hooks_RealUrl|

…

Any idea????