You should complete this form (IT PRELIM RMD) by signing it and inserting the amount of tax your expect to be liable for for that year. This amount was actually due to be paid on 31 Oct 2009.
If you feel you will have no tax to pay just insert zero.
When your accountant computes what your liability is for 2009, this amount is compared to what you paid in preliminary tax and the difference is what has to be paid or refunded by 31st Oct 2010.
Preliminary tax is basically a way of prepaying your tax for a year.
You can also set up a direct debit with Revenue for income tax to spread the payments instead of having one lump sum hitting your cashflow…
You can do DDs for VAT and PAYE/PRSI.