$('nav1').addEvent('mouseover', function(){
$('nav1').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menus1.png)');
$('navigationlegend').innerHTML = '<img src="http://www.cornelius-communication.com/medias/services.png" alt="" />';
});

$('nav1').addEvent('mouseout', function(){
$('nav1').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menut1.png)');
$('navigationlegend').innerHTML = '&nbsp;';
});


$('nav2').addEvent('mouseover', function(){
$('nav2').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menus2.png)');
$('navigationlegend').innerHTML = '<img src="http://www.cornelius-communication.com/medias/portfolio.png" alt="" />';
});

$('nav2').addEvent('mouseout', function(){
$('nav2').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menut2.png)');
$('navigationlegend').innerHTML = '&nbsp;';
});


$('nav3').addEvent('mouseover', function(){
$('nav3').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menus3.png)');
$('navigationlegend').innerHTML = '<img src="http://www.cornelius-communication.com/medias/espace-client.png" alt="" />';
});

$('nav3').addEvent('mouseout', function(){
$('nav3').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menut3.png)');
$('navigationlegend').innerHTML = '&nbsp;';
});


$('nav4').addEvent('mouseover', function(){
$('nav4').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menus4.png)');
$('navigationlegend').innerHTML = '<img src="http://www.cornelius-communication.com/medias/contacts.png" alt="" />';
});

$('nav4').addEvent('mouseout', function(){
$('nav4').setStyle('background-image', 'url(http://www.cornelius-communication.com/medias/menut4.png)');
$('navigationlegend').innerHTML = '&nbsp;';
});