Two wordpress mu installs, same settings/plugins/themes?

To a certain extent, yes.

Take a look at the WP Multi Network plugin. It allows you to have multiple, separate MU networks running off the same installation – same core, same plugins, same themes, same database.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)