How to format the amounts which are having a value of less than 1000 in excel output (xml reports)

Hi,
I am facing a problem in xml reports.
I have a column called 'Balance' in my report.
I have to format the values with comma's and decimals in the excel output.
Say,
        12345,
        2554.5,
        123     
should come as
       12,345.00,
       2,554.50.,
       123.00
I am able to do the amounts which are >= 1000, but i am not able to achieve the formatting which are less than 1000.
Means, '123' is not getting formatted, it is coming as '123' only.
I am doing the format with
"<?format-number:BALANCE;'999G999D99'?>".

And even i tried with,
"<fo:bidi-override direction="ltr" unicode-bidi="bidi-override">
<?format-number:BALANCE;'999G999D99'?>