Woocommerce_before_main_content doesnt work

Hello,

I’m building an theme on WordPress with Woocommerce but I can’t get the hook “woocommerce_before_main_content” to work.

I tryed this:
http://docs.woothemes.com/document/third-party-custom-theme-compatibility/

remove_action( 'woocommerce_before_main_content', 'woocommerce_output_content_wrapper', 10);
remove_action( 'woocommerce_after_main_content', 'woocommerce_output_content_wrapper_end', 10);

add_action('woocommerce_before_main_content', 'my_theme_wrapper_start', 10);
add_action('woocommerce_after_main_content', 'my_theme_wrapper_end', 10);

function my_theme_wrapper_start() {
  echo '<div class="full-box content-box home"><div id="page" class="center-box content"><div class="content-left">';
}

function my_theme_wrapper_end() {
  echo '</div></div></div>';
}

But doesn’t seem to do anything.
I also tryed the alternative that was posted in this forum:
https://github.com/jigoshop/Jigoshop/wiki/How-to-Properly-Wrap-Jigoshop-Content-in-your-WordPress-Theme

does somebody know what i’m doing wrong?