I'm not exactly sure what you mean by 'index page', but if you just want to redirect your users to particular page upon login based on role, you can do that with the http://drupal.org/project/rules or http://drupal.org/project/login_destination modules. If you only need redirect, login_destination is probably the best choice. But rules is so powerful, if you're going to use any of the other functionality, then you don't also need login_destination.
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I'm not exactly sure what you mean by 'index page', but if you just want to redirect your users to particular page upon login based on role, you can do that with the http://drupal.org/project/rules or http://drupal.org/project/login_destination modules. If you only need redirect, login_destination is probably the best choice. But rules is so powerful, if you're going to use any of the other functionality, then you don't also need login_destination.