mysql passwords compatibility
If you upgrade MySQL to version 4.1 or later, you may get into
authentication troubles. The password hashing mechanism was changed, and
your old passwords may not work anymore.
As a quick fix, you can edit the my.cnf configuration file, add the
following line:
old_passwords = 1
and then restart the service.
A detailed discussion about this matter, with a list of possible solutions can be found in the MySQL reference manual.
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