Looks some thing odd, i guess, you can check with SAP, if time permits, post the screen shot.
One way or other Payroll area is nothing to do with the form 941., what could guess, in the tax reporter fields, by mistake some one could have assigned the payroll area. (guessing), by looking at the nature of the problem.
since you said, u dint see this message before, thing looks much more interesting.
Warm Regards!
-Kanuku