webservice/application/views/helpers/ProfileLink.php

<?php

class Zend_View_Helper_ProfileLink extends Zend_View_Helper_Abstract
{
	public function profileLink()
	{
		$auth = Zend_Auth::getInstance();
        if ($auth->hasIdentity()) {
            $username = $auth->getIdentity()->username;
            $logoutUrl = $this->view->url(array(
            	'controller' => 'user',
            	'action' => 'logout'
            ));
            return '<a href="'.$logoutUrl.'" alt="Se déconnecter">Déconnexion : ' . $username .  '</a>';
        }
	}
}