function rubrikswitch() {
    var switcher    = document.getElementById( 'rubrikswitch' );
    var listen      = switcher.getElementsByTagName( 'ul' );
    var liste       = listen[0];
    var rubrikenTimeout = 0;
    
    switcher.onmouseover = function() {
        window.clearTimeout( rubrikenTimeout );
        liste.style.display = 'block';
    }
    
    switcher.onmouseout = function() {
        rubrikenTimeout = window.setTimeout( 'rubrikenlisteZuklappen()' , '500' );    
    }
    
    liste.onmouseover = function() {
        window.clearTimeout( rubrikenTimeout );
        this.style.display = 'block';
    }
    
    liste.onmouseout = function() {  
        rubrikenTimeout = window.setTimeout( 'rubrikenlisteZuklappen()' , '500' );
    } 
}

function rubrikenlisteZuklappen() {
    el = document.getElementById( 'rubrikswitch' )
    ul = el.getElementsByTagName( 'ul' );
    ul[ 0 ].style.display = 'none';
}

rubrikswitch();