Total Posts: 18
There are at least two changes required for whole number currencies in Magento Community (1.7.*)
1) Correct the display of currencies to format to whole numbers. The formatting happens in core/Mage/Mode/Currency.php.
See function format(), which calls formatPrecision( $price, 2 , $options, $includeContainer, $addBrackets );
2) Correct the rounding or all calculations, i.e. totals, taxes, discounts, etc. The rounding happens in core/core/Mage/Core/Model/Store.php
See function roundPrice(), which calls round( $price, 2 );
There may be more changes required for supporting more than one currency.