MSIR.0483 LOGAPPEND not valid under CMS
The LOGAPPEND parameter was specified for a port definition in an Online running under CMS. Append mode output is not correctly supported by M204CMS so LOGAPPEND will not work correctly under CMS so it is not allowed. To append to the end of a Janus Web log file, simply specify DISP MOD on the FILEDEF or M204FDEF command or APPEND on the ALLOCATE command for the log file. Under CMS there would be no real difference between APPEND and DISP MOD, anyway.