Set jQueryUiPath in Zend Framework project

in my main layout template I set jQuery paths:

if ($this->jQuery ()->isEnabled ()) {
    $this->jQuery ()->setLocalPa开发者_如何转开发th ( $this->baseUrl () . '/js/jquery/jquery-1.4.2.min.js' )->setUiLocalPath ( $this->baseUrl () . '/js/jquery/jquery-ui-1.8.4.custom.min.js' )->addStyleSheet ( $this->baseUrl () . '/js/jquery/css/custom-theme/jquery-ui-1.8.4.custom.css' );
    echo $this->jQuery ();
}

but for some reason the ui javascript file does not appear in the header, however the css for ui is included. any ideas?

solved it. ui has to be enabled

$this->jQuery ()->uiEnable();