Beginning with Release 4.0A, you can use a new user exit in FI-SL planning to perform an additional authorization validation. To use the exit, you have to create a project for SAP enhancement GLPLAN00. Within the user exit, every database record which is to be planned according to planning parameters is made available. The customer then has to decide whether any of the records presented should not participate in planning. An example is given in the SAP documentation for enhancement GLPLAN00.