shop with 2 taxes: 6% and 21%

[h-bo]

Hi am create for the first time a store with vrituemart.
And am looking for a solution for the following problem. This was asked by several people at various forums.

I have a question: I have a shop with 2 taxes: 6% and 21%
What I want is that the tax on the shipping is calculated the following way:

When chose product(s) of 6% - calculate base shipping + 6% tax
When chose product(s) of 21% - calculate base shipping + 21% tax

When chose a product of 6% AND 21% - calculate the highest (21%) tax of shipping.


Is there an override for this so that always the highest tax rate will be calculated.

Thanks h-bo