Hi, just to mention that it is technically possible to activate PSM_GEN_BUDPER1 business function while not in EA-PS 604 or higher (we have activated it by mistake in EA-PS 600..).
SAP has issued a note to prevent the activation of PSM_GEN_BUDPER1 in versions earlier than EA-PS 604 (SAP Note 1871321 - Activation check for PSM_GEN_BUDPER_1).
Also please check SAP Note 1315534 - BC Sets inconsistencies in table TKAFD if you have performed an activation of this business function with system being in a lower SP.