This boolean flag indicates whether the server is licensed to allow voicemail messages to be recorded without a length restriction. An admin fielding complaints about voicemail messages being cut short can check this flag to determine whether the limitation is a licensing restriction rather than a configuration setting like cueMboxMessageSizeMax. If ciscoUnityLicMaxMsgRecLenIsLic is false, the admin knows message length caps on this server are enforced by the license itself and cannot simply be raised through configuration alone.