theme currency default is wrong

Perhaps this is intentional; but i think a minor bug.

I was searching to find a theme_currency($amount, $currency) function where i could simply pass value and the currency and end up with a formatted value:

so theme_currency(18000, 'usd') ===> $18,000.00

but all i could find is theme_currency_api_amount($amount, $attributes) which requires me to pass a bunch of attributes. A little more digging and i found that this:

$c = currency_api_get_currencies();
$tc = $c['USD'];

would return a set of default attributes for my currency.. pretty cool.

so i could then simply do this:

echo theme_currency_api_amount(18000, $tc);

this works very nice except that 'decimals' doesnt get handled correctly.

currency_api_get_currencies() returns 'decimals' as the array key whereas
theme_currency_api_amount() uses 'decimal' as the array key.

Is this an intentional difference or a bug?