Thought I'd share this one, maybe it could become a Solution!!!:
A new setup was apparently working and nothing changed (??) but mail stopped being delivered to Scalix with 550 User unknown 5.1.1 errors.
Omstat -s showed the Service Router as partially aborted. Restarted it and we got the following errors reported at level 9 and level 11 logging.
SERIOUS ERROR Service Router(Service Router) 08.17.06 13:35:08
[SYS 43] Identifier removed
Current errno value: 43
<- Mll_ReadEntry
<- Mll_ReadMessage
<- sr_ScanMessageList
-> Mll_UnLockFile
<- Mll_UnLockFile
<- sr_LoadDeferMsgs
-> sr_ProcessMemoryList
<- sr_ProcessMemoryList
-> Q_SetTimeOut
<- Q_SetTimeOut
-> Q_GetMsgFromQueue
-> Q_ClearTimeOut
<- Q_ClearTimeOut
<- Q_GetMsgFromQueue
-> Q_CloseQueues
<- /build/10.0.1.3/src/lib/ombase/os/os_msg.c:92[1,43]
SERIOUS ERROR Service Router(Service Router) 08.17.06 13:36:23
[OM 5187] Child process (Mapper) failed.
Current errno value: 2
-> rsl_GetRuleValue
<- rsl_GetRuleValue
-> rsl_GetRuleValue
<- rsl_GetRuleValue
-> rsl_GetRuleValue
<- rsl_GetRuleValue
<- rsl_GetRuleSet
<- sr_CheckForVirusRule
-> vs_ScanInit
-> vs_ScanActive
<- vs_ScanActive
-> vs_omScanInit
-> vs_GenericScanInit
<- /build/10.0.1.3/src/lib/rsl/rsl_match.c:488[100,5187]
<- /build/10.0.1.3/src/lib/rsl/rsl_match.c:755[100,5187]
<- /build/10.0.1.3/src/lib/rsl/rsl_match.c:1465[100,5187]
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[root@mailmaster logs]# omshowlog -p 1 -l 11
REPORT Service Router(Service Router) 08.17.06 14:12:55
[OM 10289] === Tracing - Escaped at /build/10.0.1.3/src/lib/rsl/rsl_match.c:755 [100:5187]
REPORT Service Router(Service Router) 08.17.06 14:12:55
[OM 10289] === Tracing - Escaped at /build/10.0.1.3/src/lib/rsl/rsl_match.c:1465 [100:5187]
SERIOUS ERROR Service Router(Service Router) 08.17.06 14:12:55
[OM 5187] Child process (Mapper) failed.
Current errno value: 2
<- cust_GetCustomiseInfo
<- cust_PresentAndTrue
-> vs_ScanActive
<- vs_ScanActive
-> vs_omScanInit
-> vs_GenericScanInit
-> rsl_MapVScanInit
-> rsl_FormFullRulePath
<- rsl_FormFullRulePath
-> rsl_ReuseOrInvokeMapper
-> rsl_FormFullRulePath
<- rsl_FormFullRulePath
-> rsl_InvokeMapper
<- /build/10.0.1.3/src/lib/rsl/rsl_match.c:488[100,5187]
<- /build/10.0.1.3/src/lib/rsl/rsl_match.c:755[100,5187]
<- /build/10.0.1.3/src/lib/rsl/rsl_match.c:1465[100,5187]
REPORT Service Router(Service Router) 08.17.06 14:12:55
[OM 7901] Defer Mail Manager Started Up
Found some other cases in Forum related to errors 5183 and 5181 related to the Service Router and ClamAV.
Had the customer check what the /etc/passwd file showed for Scalix and ClamAV user/groups. ClamAV was setup as a separate group and user. Had him change the clamav user to the same group as scalix. i.e.
/etc/passwd:
scalix:x:100:101:Scalix User:/var/opt/scalix:/bin/true
clamav:x:104:103:ClamAV database admin:/etc/nologin
changed to:
scalix:x:100:101:Scalix User:/var/opt/scalix:/bin/true
clamav:x:104:101:ClamAV database admin:/etc/nologin
Restarted the service router and this time it started and all the mail moved that was on the router queue.