I use a payment module here in Japan for my credit card purchases, Remise payment.

It works fine until I have a coupon and then it gives me an error of incorrect total amount.

What is going on is like this. You have a price of 849 yen. 50% off coupon. So the price goes to 425 (rounds up). This 425 is the price that shows up on the total.

Then when it goes to pass all the information to Remise, they are getting an about of 424.5 yen, and in yen you can't do the .5...so I get the error of incorrect total amount. I need to find out were this amount is getting passed from and how to fix it.

Might be hard, but if anyone can give me some hints that would be great!