Service tax on security charges??

Dear members,

As per new reverse charge mechanism, if Service provided by Security agency (Proprietor) to a company then, service tax laibility is on service reviever is 75% and on proprietor it is 25%.

But my question is that, what if the proprietor has charged 100% service tax in invoice?? Whether the company is liable to pay 75% of Service tax or not? if yes then, isn't the total tax will be paid more than 100% to the govt revenue.

Or we have to ask to the service provider to change the Invoice bill and charge 25% service tax only..

Please clarify me..

Thanks in advance..