IFNULL returning NULL when there"s really a value!

Hi,

I have a column SALE_PRICE, which is a FLOAT type. I have a row that
contains the value "0.25", however when I execute this statement

SELECT IFNULL(SALE_PRICE, 'Empty') FROM PRODUCTS WHERE PRODUCT_ID = 2

I get the result "Empty" instead of ".25". Why is that? What can I do
to ensure that I get the value ".25" instead of "Empty"?

Thanks, - Dave