Migrating Travel Expenses to Separated Payroll

Hi.

I'm just trying to create an IDoc (type HRTRVL03) and for that I am executing the report RPRPAY00 : Transfer Travel Expenses to Payroll.

But I get no results. Only the following message:

"Integration with payroll not active (Feature TRVPA)

Program to Transfer Travel Expenses to Separate Payroll accounting system' can not be used.

Error during initialization of transfer."

Can you help me with this?

Thanks.