Requirement to make PAN number mandatory for processing payroll

I have a client requirement that payroll should be processed only for those persons for whom PAN number is available.One way to do this would be a custom report which could give a list of persons for whom the PAN number is not available & to lock the Payroll in IT 0003 for such persons whose PAN number is not anailable.

But is there any other way to configure the system so that the system will not run payroll automatically for persons whose PAN number is not available?

Useful answers will be rewarded.

Thanks,

Ravi.