Operation is unsupported for version of database.

  Explanation:  You tried to do something with a pre-V3.1 database
  that requires version 3.1 or higher.  This can happen when
  Rdb/Remote is used to access a database of a different version
  than that of the database system.

  User Action:  Convert the database to the current version of Rdb
  or do not attempt the operation that caused the problem.