Uprocs executing many UXSET MSG running in a session simultaneously are randomly aborted

Issue/Introduction:

Error Message :
Following errors in the job log:

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Command in error (code: 44)
Fatal error reading General table
uxset : status 134461002 , This node is unknown
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In the universe.log we can find

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Créé par: Pascal OSTHUS-BUGAT (09/03/2015 14:26)
Error messages in the customer universe.log

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| 2015-02-26 05:00:17 |ERROR|X|IO |pid=51794.16595| k_define_user_owls_key | UXOS_GetUsrUidGrp(aacedul) returns error ª3025|
| 2015-02-26 05:00:17 |ERROR|X|IO |pid=51794.16595| o_Auth_ILocal_OWLS_Check_ | Error checking key /qopensys/orsyp/DU_ARC/data/exp/local/AS400PR1.XXXXXXX.CA_bs_XXXXXXXX.key (-1)
| 2015-02-26 05:00:17 |ERROR|X|IO |pid=51794.16595| o_Auth_ILocal_OWLS_Trt_Ke | o_Auth_ILocal_OWLS_Check_File returns error ª-1|
| 2015-02-26 05:00:17 |ERROR|X|IO |pid=51794.16595| k_select_accept_aut | kTrtHelloRequest in error ª-1|
| 2015-02-26 05:00:17 |ERROR|X|IO |pid=51794.16595| u_io_thread_trt | New client 99 (uxset/XXXXXXon 192.168.16.21) authentication failed: Hello request error (Hello request error)
| 2015-02-26 05:00:17 |ERROR|X|uni|pid=67723.571| k_handshakeHello | hello request in error, mat is ª3|
| 2015-02-26 05:00:17 |ERROR|X|uni|pid=67723.571| o_connect_auth | k_connect_auth_timeout returns error ª-1|
| 2015-02-26 05:00:17 |ERROR|X|uni|pid=67723.571| u_io_callsrv_gen | o_connect_auth in error ª-1|
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Patch level detected:Dollar Universe 6.3.00
Product Version: Dollar.Universe 6.3.01

Description :If several similar uprocs run simultaneously, all of them executing an important number of UXSETMSG instructions, from time to time it can happen, that one or the other job aborts. The related job may remain in MSGW on the AS400 system.

Cause:

Cause type:
Defect
Root Cause: N/A

Environment:

OS: IBM AS/400
OS Version: V6R1/V7R1

Resolution:

Update to the fix version listed below or a newer version if available.

Fix Status: Released

Fix Version(s):
Component: Application.Server
Version: Dollar.Universe 6.4.21

Additional Information:

Workaround :
N/A