I've found some details below. It might be none of them!.
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Option 11C upgraded to rls 5.50J
Repeated BUG253s seen during the day eg:
mplr26182 was provided and stopped the BUGs
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BUG5763 or BUG253
Bug 5763 and or BUG253 being generated since upgrade to release 5.
MPLR27845 which was intentionally to created to fix BUG5763, fixes a pointer which is a reason for both BUG253 (for this RAS) and BUG5763 in procedure SETCFWDN.
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ITG inter unable to make calls over the network.
BUG253 BUG0253 in history file.
Scenario.
Every now and then customer complains of not being able to make calls over the ITG network.
No circuit channel available message seen on originating site DCH messaging.
Traces on the other site indicate the call reaches the ITG card (h323SessionShow) but never send the call to the DCH and onward to the M1.
BUG253 seen in history file (now and then, not during the call)
It was found that by changing NCRD to NO cured the problem. If NCRD is not needed (it shows status of call forwards etc on the far away site) then this fix will do. Otherwise a more permanent fix will be required. (Exact scenario is not known).
All the best
Firebird Scrambler
Meridian 1 / Succession and BCM / Norstar Programmer in the UK
If it's working, then leave it alone!.