Changing the DB_NAME, HOW ?

I got a problem.

i got a NT server with 5 oracle database (7.2.2.4 version). Now yout thinking that's no problem. But all the databases have the same name (default value : oracle). I i try to change the db_name in the init.ora is receive a error that the name is not the same as the controlfile is expecting and the db will not start.

Is there a way to change this easy ?

Thank you !

PS

within a few weeks we will migrate to 7.3.3. !

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