If you upgrade a CSD from CICS TS 2.2 to CICS TS for z/OS, Version 3.1 level, if it is shared by any CICS TS 2.2 regions
other than that being upgraded, include the DFHCOMPA resource group (supplied
with CICS TS for z/OS, Version 3.1) in the startup group list of these regions. DFHCOMPA
is a compatibility group that provides a definition of DFJIIRP, the default
request processor program, that can be used by a CICS TS 2.2 region when sharing
a CICS TS for z/OS, Version 3.1 CSD.
This step is necessary because, in CICS TS for z/OS, Version 3.1,
the JVM profile used by DFJIIRP is DFHJVMCD. In CICS TS 2.2, it is DFHJVMPR.