CORBA25 — Inconsistent text for unknown system exception

In document 01-01-01, there are the following paragraphs which seem
contrary to one another regarding the minor code to be used when an
ORB receives an unrecognized system exception.

4.11.2
Vendors may define non-standard system exceptions, but these exceptions are
discouraged because they are non-portable. A non-standard system exception, when
passed to an ORB that does not recognize it, shall be presented by that ORB as an
UNKNOWN standard system exception. The minor code and completion status from
the unrecognized exception shall be preserved in the UNKNOWN exception.

15.3.5.5 Exception
Exceptions are encoded as a string followed by exception members, if any. The string
contains the RepositoryId for the exception, as defined in the Interface Repository
chapter. Exception members (if any) are encoded in the same manner as a struct.
If an ORB receives a non-standard system exception that it does not support, or a user
exception that is not defined as part of the operation's definition, the exception shall be
mapped to UNKNOWN, with standard minor code set to 2 for a system exception, or
set to 1 for a user exception.

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