PeopleSoft v9.2 Supplemental Tax calculation

All - I have a paycheck with Taxable Gross for FWT of $4,012.45. Out of this total, $1,015.41 is from bonus earnings which is configured as Supplemental Tax Method on the Earnings Code table. Employee's tax data is Married with Allowance of 1. I assume Peoplesoft would use the annualized method to calculate the Taxable Gross of $2,997.04 ($4,012.45 - $1,015.41) which comes out to be $268.18 FWT, then add the bonus tax by calculating $1,015.41 * 22% = $223.29. So the total FWT should be $491.57. However, the paycheck shows FWT of $487.37.