Error in Karl Grabe's Tax calculator?

There appears to be an error in the formula for calculating income tax for married couples.

Take an example of a married couple Salary 1 = 75000
Salary 2 = 28000 in tax year 2003

KG's Calculator taxes the first €56000 @ 20% and the remaining @ 42%
ie 56k @ 20% = 11200
47k @ 42% = + 19740 = 30940

Less Married Allow. 3040
less personal credits x 2 + 1600 = 4640
Tax Payable 26300

According to the example on their website - Revenue taxes the first €37000 @ 20% for the higher earner
and the remainder at 42%. As it is below the threshold Salary 2 is taxed at 20%
ie Salary 1 37000 @ 20% = 7400
Salary 1 38000 @ 42% = 15960
Salary 2 28000 @ 20% = 5600 = 28960

Less Married Allow. 3040
less personal credits x 2 + 1600 = 4640
Tax Payable 24320

Difference of €1980

Are my calculations correct or is this just wishfull thinking?

The 20% band for a married couple each earning €28K or more is €56,000. The increased band of €37,000 is only relevant for a married couple with one income. It ceases to apply when the other spouse earns €19,000 or more.

So it was wishful thinking after all - Thanks Tommy.