VAT is not correct calculated in case of discount

[thorpi]

Helo,
first excuse my bad english - I'm a German.
I use Joomla 2.5.4 with VM 2.0.6.
My problem: I have a payment method with 3 % discount. The calculation applies and indicates it only to the whole price but not to the responding VAT.
The amount of VAT isn't correct therefor.
Can anybody help me?
Thanks
thorpi

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