Multi-currencies error or bug

It is only used for a single currency. I set a checkbox for 5.99 USD. When people change the currenty to GBP, CNY, JPY, EUR, and it still show the 5.99 GBP, 5.99 CNY, 5.99 JPY, 5.99 EUR. The prices is only a number, and it is never changed by the currency rate. eg. I am selling fragile glass cup. I need buyers check the box from a checkbox or select one type of box from a raido buttion group. The box price should be updated or changed by buyer’s currency.