The following error values are available as a part of the SIP Client API:
KErrSIPMalformedMessage, KErrSIPInvalidRegistrarResponse, KErrSIPRequestPending, KErrSIPInvalidTransactionState, KErrSIPInvalidDialogState, KErrSIPInvalidDialogRequest, KErrSIPInvalidDialogResponse, KErrSIPTransportFailure, KErrSIPNoAckReceived, KErrSIPInvalidRegistrationState, KErrSIPInvalidContact, KErrSIPResourceNotAvailable, KErrSIPResolvingFailure, KErrSIPForbidden, KErrSIPMaxCompartmentsInUse, KErrSIPTerminatedWithResponse, KErrSIPOutboundProxyNotResponding, KErrSIPInvalidURIType, KCRUidSIP.
The following are the SIP Central Repository (CenRep) entries:
KSIPTransactionTimerT1, KSIPTransactionTimerT2, KSIPTransactionTimerT4.