Comment 16 for bug 868839

We also have this problem in Quebec (Canada) where the rate is 9,975% (0.09975) so we need to compute the taxes with a rate precision of 5, but the total amount of an invoice must be rounded to 2 decimal either by line or globally. Here is the state reference : http://www.revenuquebec.ca/en/entreprise/taxes/tvq_tps/calcul-taxes.aspx