New Service Tax Implem. Error

Hello,

As you know, Service tax rate is changed to 10% from 12% ,I want to keep both of previous rate & present rate based on the date tax applied for.

I want that my system will calculate the Service tax as on the basis of Bill creation date & service tax rate of that date.

But, when I was trying to create another service tax rate with presence of old one,the system showing me error like--- "Could not commit Transaction Sales Tax Authorities(OSTA)"

How will I do this?

Rgds

Subrata