How to add custom attribute to select options?

Question

Is it possible to add custom values to select options e.g. in configurable products?

I need to add the sku of the option to the option, so that it will become

<option id="354" price="10" sku="my_sku">Option name</option>

I figured out that the Block Class of the Select is Mage_Catalog_Block_Product_View_Options_Type_Select, so I overrided the class but I don't know which code I have to edit.

I found the definition of addOption in Mage_Catalog_Model_Product_Option but there is no big logic.

Edit: This is not the right definition. The right definition is in the Block class Mage_Core_Block_Html_Select

/**
 * Add an option to HTML select
 *
 * @param string $value  HTML value
 * @param string $label  HTML label
 * @param array  $params HTML attributes
 * @return Mage_Core_Block_Html_Select
 */
public function addOption($value, $label, $params=array())
{
    $this->_options[] = array('value' => $value, 'label' => $label, 'params' => $params);
    return $this;
}

Cache is deactivated.

Answer 1

I figured it out. The definition of addOption is in Mage_Core_Block_Html_Select, there are 3 parameters.

 * @param string $value  HTML value
 * @param string $label  HTML label
 * @param array  $params HTML attributes

You can pass new attributes by passing them as array via the 3rd parameter $params.

$select->addOption(
    $_value->getOptionTypeId(),
    $_value->getTitle() . ' ' . $priceStr,
    array(
        'price' => $this->helper('core')->currencyByStore($_value->getPrice(true), $store, false)
        , 'sku' => $_value->getSku()
    )
);