Query relating to Service Tax

Can a company adjust its Service Tax input credit of earlier years (2006-07, 2007-08,2008-09, 2009-10) against its Excise Duty payable of this year(2010-11)?

- if the unit in under cenvat credit of service tax scheme i.e not availing exemption of 10L per year then accumulated balance he can use in payment of service tax for taxable services "tendered" or cenvat duty for exiseable goods "cleared"

If it can adjust the same means will the answer be the same for the below case:

Its Service tax Payable part of the above said years is unpaid until today and got permission  from service tax Dept for the late payment of the  payable portion because it is a loss making concern(for the above said years).

- Service Tax payable means u have provided taxable services and the receipent of the service would be eligible for service tax credit. 

- if the Service is related to import of services / GTA, then input credit may not be available as it had to be taken on date of service payout and tax payout, not in later years..

Thanks in advance.