**Calculation error when applying coupon..**

I notice there is a calculation error when I am applying a coupon. I put a coupon in with a value of 10%. When it goes to the shopping cart it says this:

Subtotal 34.95 USD

Discount -3.50 USD

Total 31.46 USD

The total should be 31.45. It appears it is rounding the coupon amount from 3.495 which makes it 3.50. This is fine if it used this amount and then subtracted it from 34.95. It appears it is using the full amount of 3.495 and subtracting, which would give a total of 31.455, and then again rounding it, which would give 31.46.

Just to check, I changed the quantity to 3, and here is the result:

Subtotal 104.85 USD

Discount -10.49 USD

Total 94.37 USD

Again, the total should be 94.36.

Can you point me to where the calculation is being done and perhaps give a code fix I could insert to correct this problem.

Thanks

Doc