Penalty on service tax

Hi,

I have a querry regarding default in filling of Service Tax Return, if a company is having more than one registrtation numbers, the how the penalty is panalty is payable, whether it is seperately payable for every different registarion no. (i.e every different return) or it is payble only once for a company for all different registartion nos.

Please give reply with references if possible.

Thanks