Finally I find the error . It was a sentence in functions_taxes.php that is wrong and I still don't no why. If somebody have an idea it will be appreciate. The last sentence give me an error.( $tax is the value that cause the error. Strange because it was tested > then 0 before calling the las functions)
Thanks.
////
// Add tax to a products price based on whether we are displaying tax "in" the price
function zen_add_tax($price, $tax) {
global $currencies;
if ( (DISPLAY_PRICE_WITH_TAX == 'true') && ($tax > 0) ) {
return zen_round($price, $currencies->currencies[DEFAULT_CURRENCY]['decimal_places']) + zen_calculate_tax($price, $tax);
} else {
return zen_round($price, $currencies->currencies[DEFAULT_CURRENCY]['decimal_places']);
}
}
// Calculates Tax rounding the result
function zen_calculate_tax($price, $tax) {
global $currencies;
// $result = bcmul($price, $tax, $currencies->currencies[DEFAULT_CURRENCY]['decimal_places']);
// $result = bcdiv($result, 100, $currencies->currencies[DEFAULT_CURRENCY]['decimal_places']);
// return $result;
return zen_round($price * $tax / 100, $currencies->currencies[DEFAULT_CURRENCY]['decimal_places']);
}



