vat calculation

[WILLIAM GREENE]

On our in-house system, we calculate total vat based on the sum of the net value of all the line items in the invoice. Sage calculates the total vat based on the sum of the individual vat amounts per line item. This results in differences in vat due to rounding errors . The total vat difference is maybe only a few cents but I have to have to get rid of it somehow. Is it possible in sage to change the point at which vat is calculated? I can't find it under business settings. I tried using the tax-analysis part of the invoice but the api says it's not allowed. Maybe I need a fudge factor such as adding a "vat adjustment" line item.

Thanks, Bill