Hi

I have a problem with my cupons calculating the discount wrong. Exactly where the calculation goes wrong, I'm not entirely sure about.

Example 1:

Item X = 98,00 inc VAT
Add discount cupon 30%
calculates discount to 26,46 -> should be 29,40

Settings in the cupons orders total module =
Include Shipping = False
Include Tax = False
Recalculate Tax = None
Tax Class = 25%


Example 2:
Item X = 98,00 inc VAT
Add discount 30%
Calculates discount to 35,28 -> Should still be 29,40

Settings:
Include Shipping = False
Include Tax = True
Recalculate Tax = none
Tax Class = 25%

In short, any setting in the cupons module gives either 26,46 or 35,28 in discount, both of which is wrong, making the cupons useless.

Anyone have any ideas on where to start looking for where the problem exist?