For the notification user system try : http://community.elgg.org/plugins/734185/1.4.2/multiple-be-tom-friends

Also you can create a site message system, which will show the latest site news in the user dashboard.

I use a "sticky" notice on top of the river to display info about important changes etc. The feature exist in the 3c river plugin.

Thanks colleagues! Finally, I opted for the be tom plugin because it avoids to unfriend the Notifications User. Thanks again for yout help.

Yes, by upgrading to 1.8.12

I have version 1.8.13 and the elgg-state-selected class won't come up for the custom menu items (elgg-admin ->Appearance->Menu Items).
Any ideas?
I guess it was lost by upgrading from 1.8.1 to 1.8.9.

Thanks in Advance

Tobi

I solved it now with jQuery:

$(document).ready(function() {
    path= window.location.pathname;
    if(path.indexOf( 'activity' )>-1){
        $(".elgg-menu-item-custom4").addClass('elgg-state-selected');
    }
    if(path.indexOf( 'agpages/cat/about' )>-1){
        $(".elgg-menu-item-custom5").addClass('elgg-state-selected');
    }
   ...
})