Problem whit product variable and custom theme

Hi,

i’m having issue whit product variable on my site.
I have a very simple custom theme and i have declared woocommerce whit the function

if ( ! function_exists( 'miotema_add_woocommerce_support' ) ) {
function miotema_add_woocommerce_support() {
	add_theme_support( 'woocommerce' );
}
}
add_action( 'after_setup_theme', 'miotema_add_woocommerce_support' ); 

in function.php. All work except a variable product page. When i select an option from the form select nothing appear (no photo, no price, no description change). If i change theme all work so i think there is a problem with my theme.

Any solution, please?

you can see the problem here:

http://blog.agricolatricarico.it/prodotto/prodott-variabile/

Thank you for your help!!

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