Javascript or Php code for multiple currencies in our site

The project should be conducted within 48 hours after the project is awarded. We have a javascript in our wordpress site that changes the currency when a client press a specific flag. Apparently there is some problem with creating cache in the browser that prevents changing the currency and price. You may use the current javascript or use yours This is what we need : 1) Your code needs to automatically detects the zone of the visitor from the IP address. 2) Currently we have 4 zones and the currency and phone number should be updated based on that. 3) The flags of the countries are shown above the design so if the visitor decide to change the currency they should be able to click on the flag. You should be able to work with Wordpress, Javascripts, CSS. You MUST be able to communicate with us in "English" and talk with us via Skype, GTalk, or Phone after the project is awarded.