I defined scratch subpools in CA 1 using TMOSCRnn and TMONSMnn members. The IBM mount messages are correctly intercepted and the TMS002 messages contain the correct scratch subpool. However, the subpool from the TMS002 mount message is not honored by the MDL.
Bus-Tech Mainframe Data Library (MDL) retrieves the subpool name from the 3480 pod display, not from the TMS002 mount message. In order to have the CA 1 scratch subpool displayed on the 3480 pod display, install the CA 1 message display exit using usermods CL05219 and SMP3480. See installation Guide '4.21 Step 20 - Install 3480 Message Display Exit' for details.