[TYPO3-shop] Tax calculation error (rounding problem?)

[Ryan Hayle]

I'm having trouble with the tax calculations in the shop.  I've set 
plugin.tt_products.TAXpercentage = 6.00, however, take the following 
example:

Product P1 costs 1.20, P2 is 1.60.

123*P1 + 456*P2 = 877.20
877.20*.06 = 52.632

The shop shows tax to be 54.21!

I'm not sure where the extra 1.578 went!  This is mostly noticeable on a 
large scale, but I did notice this:

If I only have 2 P2 (3.20), the calculated tax is 0.20 when it really 
should be 0.192. It is rounded up instead of down.  Is this the expected 
behaviour?  Is the tax calculation impacted by using different article 
prices?  My prices are entered without tax included, and I have no tax 
on shipping or payment methods.

Any thoughts on this?

Thanks,
Ryan