I have done exactly as you suggest and I get an error "The total amount you entered doesn't equal your reported exempt-interest dividends in Box 11 of your 1099-DIV."
I also used my fund documentation to calculate the percentage for all states (47) with dividends reported and entered them all, one-by-one, such that the total equals exactly the reported exempt-interest dividends in Box 11 of my 1099-Div and I still get the same error. I have tried to split a few arbitrarily such that the total is the same as Box 11 and that seems to work. It just seems that if one gets over some number of rows that the application fails to add them up and throws and error.
