[Plugin: WooCommerce] How to customize the single product variations?

Hi,

how can I add the content of a custom tab to the single product variation?

My function to display Custom Tab on Frontend of the Website for WooCommerce 2.0 is:

add_filter( 'woocommerce_product_tabs', 'woocommerce_product_custom_tab' );		

function woocommerce_product_custom_tab( $tabs ) {
   global $post, $product;

   $custom_tab_options = array(
	'enabled' => get_post_meta($post->ID, 'custom_tab_enabled', true),
	'title' => get_post_meta($post->ID, 'custom_tab_title', true),
			    'content' => get_post_meta($post->ID, 'custom_tab_content', true),
		    );

		    if ( $custom_tab_options['enabled'] != 'no' ){
			    $tabs['custom-tab-first'] = array(
				    'title'    => $custom_tab_options['title'],
				    'priority' => 25,
				    'callback' => 'custom_product_tabs_panel_content',
				    'content'  => $custom_tab_options['content']
			    );
		    }

		    return $tabs;
	    }

      /**
      * Render the custom product tab panel content for the callback 'custom_product_tabs_panel_content'
      */
	function custom_product_tabs_panel_content( $key, $custom_tab_options ) {

		  echo '<br />';
		  echo ' <input type="checkbox" name="custom_tab_title" value=' . $custom_tab_options['content'] . '/>' ;
		  echo ' <label> ' . $custom_tab_options['content'] .  '</label> ';

		  // echo '<h2>' . $custom_tab_options['title'] . '</h2>';
		  // echo $custom_tab_options['content'];

	  }

the content of the custom tab should be placed at the right content side.
I think the content must be placed in the wp-contents/theme/woocommerce/singe-product/add-to-cart/variations.php but I don′t know the right function or hook.

Thank you!