Interest on interest payable on service tax?

I would like to know whether Interest will be charged on Interest already payable on Service Tax Liability? I have paid only Liability but Interest Payment is still pending, if I get a notice for payment, would they charge Interest on the same? The second question is, if Interest is charged on Interest, then from which date will it be calculated? From the date of Service Tax liability paid or from the Interest already accruing? Request your kind help in throwing light into this matter. Thank You.