Old MySQL Client does not support authentication...

http://dev.mysql.com/doc/refman/5.0/en/old-client.html

Warning: mysql_connect(): Client does not support authentication protocol requested by server; consider upgrading MySQL client in C:\Program Files\Apache Group\Apache2\test\phpBB2\db\mysql4.php

Reset the password to pre-4.1 style for each user that needs to use a pre-4.1 client program. This can be done using the SET PASSWORD statement and the OLD_PASSWORD()function:

mysql> SET PASSWORD FOR
    -> 'some_user'@'some_host' = OLD_PASSWORD('newpwd');

Alternatively, use UPDATE and FLUSH PRIVILEGES:

mysql> UPDATE mysql.user SET Password = OLD_PASSWORD('newpwd')
    -> WHERE Host = 'some_host' AND User = 'some_user';
mysql> FLUSH PRIVILEGES;