Users identified by passwd may also be identified externally

With Oracle 7.0.15.4 (Solaris 2.3), when we define an user with the command: create user toto identified by titi
If an Unix toto exist, it may execute sqlplus / and enters in the database.

With another instance and version (7.0.16.x), with the same command of the user's creation, the user Unix toto may not enters in the database without giving its password (titi in the example).

Is it a bug or a known feature or a different parameter ?

Suggestions are welcome.

Thanks and regards,

        Alain V.

Alain VIRET, EDDB-VIL     |
Union de Banques Suisses  | 
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