error in mysql user password

I am using Ubuntu 10.10 and I installed phpmyadmin from synaptic package manager.

But i did not put any password on mysql root user and phpmyadmin user.

Later, i tried to log into phpmyadmin with user root and no password it get error

Login without a password is forbidden
by co开发者_开发百科nfiguration (see AllowNoPassword)

And chage password in mysql is not working, I tried to update password using password('pma') in passsword field in user table of mysql database, but still I am not being able to log in from console.

How to change mysql password, and where is this phpmyadmin configuration file.

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I'm not sure about the larger problem, but phpMyAdmin's configuration file is stored in phpMyAdmin/config.inc.php. The username and password can be found on line 85:

85  $cfg['Servers'][$i]['user']          = 'root';      // MySQL user
86  $cfg['Servers'][$i]['password']      = 'root';      // MySQL password (only needed
87                                                      // with 'config' auth_type)