Error forking ipcshm listener thread

Hello, IDS 9.30 FC3 AIX 5.2 I had an instance which had been running for months. Yesterday I decided to test connection multiplexing by making the recommended two changes: (1) add a new NETTYPE with 'sqlmux', and (2) add option "m=1" in the sqlhosts file for the line referring to the servicename for the instance. With these changes made, the instance did come up OK. Today, I wanted to set the instance back in the previous state. So I undid the two changes (mentioned above) and tried to bring up the instance. And I get an error at the stage of "forking the ipcshm listener threads". I tried putting the "multiplexing" info back and bringing up the instance. I still get the same error on forming ipcshm listener threads. Other instances on the same machine can be 'bounced' without problems. Any ideas, anyone? Here's the output of "oninit -v" -------------------------------- informix:neptune> oninit -v Checking group membership to determine server run modesucceeded Reading configuration file '/apps/informix/etc/onconfig.aps6'...succeeded Creating /INFORMIXTMP/.infxdirs ... succeeded Creating infos file "/apps/informix/etc/.infos.aps6" ... "/apps/informix/etc/.co nf.aps6" ... succeeded Writing to infos file ... succeeded Checking config parameters...succeeded Allocating and attaching to shared memory...succeeded Creating resident pool 14268 kbytes...succeeded Creating buffer pool 160000 kbytes...succeeded Creating buffer pool 8 kbytes...succeeded Initializing rhead structure...succeeded Initializing ASF ...succeeded Initializing Dictionary Cache and SPL Routine Cache...succeeded Bringing up ADM VP...succeeded Creating VP classes...succeeded Onlining 3 additional cpu vps...succeeded Onlining 2 IO vps...succeeded Forking main_loop thread...succeeded Initializing DR structures...succeeded Forking 3 'ipcshm' listener threads.../u/informix informix:neptune> And here's the last part of the log file ---------------------------------------- 11:00:54 Informix Dynamic Server Started. 11:01:00 VP pid=1142964 cannot change priority, errno=1 11:01:00 Could not disable priority aging: errno = 1 Fri May 7 11:01:00 2004 11:01:00 Event alarms enabled. ALARMPROG = '/apps/informix/etc/no_log.sh' 11:01:01 Booting Language <c> from module <> 11:01:01 Loading Module <CNULL> 11:01:01 Booting Language <builtin> from module <> 11:01:01 Loading Module <BUILTINNULL> 11:01:01 VP pid=467068 cannot change priority, errno=1 11:01:01 Could not disable priority aging: errno = 1 11:01:02 VP pid=413736 cannot change priority, errno=1 11:01:02 Could not disable priority aging: errno = 1 11:01:02 VP pid=962748 cannot change priority, errno=1 11:01:02 Could not disable priority aging: errno = 1 11:01:07 AIX MP latch code enabled 11:01:07 Requested shared memory segment size rounded from 1724KB to 1728KB 11:01:07 Requested shared memory segment size rounded from 1724KB to 1728KB 11:01:07 Dynamically allocated new message shared memory segment (size 1728KB) 11:01:07 Requested shared memory segment size rounded from 1724KB to 1728KB 11:01:07 Dynamically allocated new message shared memory segment (size 1728KB) @ 11:01:07 Requested shared memory segment size rounded from 1724KB to 1728KB 11:01:07 Dynamically allocated new message shared memory segment (size 1728KB) 11:01:07 Assert Failed: shm_be.c, line 3578, thread 12, errno=1, could not open shm file. 11:01:07 Informix Dynamic Server Version 9.30.FC3 11:01:07 Who: Session(6, informix@, 0, 0) Thread(12, sm_listen, 0, 4) File: neterrb.c Line: 658 11:01:07 stack trace for pid 413736 written to /tmp/af.3f4a4b2 11:01:07 See Also: /tmp/af.3f4a4b2 11:01:09 neterrb.c, line 658, thread 12, proc id 413736, shm_be.c, line 3578, t hread 12, errno=1, could not open shm file.. 11:01:09 Fatal error in ADM VP at mt.c:12008 11:01:09 Unexpected virtual processor termination, pid = 413736, exit = 0x100 11:01:09 PANIC: Attempting to bring system down ------------------------- Thanks. Alanoly Andrews.