AJAX Onepage Checkout Modification

[login to view URL] The above module is working fine. However need the following modification: Our old [login to view URL] payment module that works fine with the regular OSC checkout does not work with the Ajax solution. We need our old module to be modified to work with the Ajax checkout. New [login to view URL] module provided with this contribution to work with the Ajax checkout however it lacks some of the custom code we had added to our old module. The second modification is to add to the ajax checkout page the coupon gift voucher option. Oscommerce Standard checkout already has the code we just need to create a solution that will work with Ajax checkout. Thanks