ns4 = (document.layers)? true:false
ie4 = (document.all)? true:false
 
accueil0 = new Image();
accueil1 = new Image();
pres0 = new Image();
pres1 = new Image();
activites0 = new Image();
activites1 = new Image();
reseau0 = new Image();
reseau1 = new Image();
contact0 = new Image();
contact1 = new Image();


// chargement des images dans le cache

accueil0.src ="images/menu_accueil_1_fr.gif" 
accueil1.src ="images/menu_accueil_0_fr.gif" 
pres0.src ="images/menu_presentation_1_fr.gif" 
pres1.src ="images/menu_presentation_0_fr.gif" 
activites0.src ="images/menu_activites_1_fr.gif" 
activites1.src ="images/menu_activites_0_fr.gif" 
reseau0.src ="images/menu_reseau_1_fr.gif"  
reseau1.src ="images/menu_reseau_0_fr.gif"   
contact0.src ="images/menu_contact_1_fr.gif"  
contact1.src ="images/menu_contact_0_fr.gif" 


// survol des images
function show(sens) {
switch(sens) {
		case "entree0" :
   document.e0.src = accueil1.src   
   break;
   case "sortie0" :
 document.e0.src = accueil0.src
       break;

		case "entree1" :
   document.e1.src = pres1.src   
   break;
   case "sortie1" :
 document.e1.src = pres0.src
       break;
       	case "entree2" :
   document.e2.src = activites1.src  
   break;
   case "sortie2" :
 document.e2.src = activites0.src
       break;
	case "entree3" :
   document.e3.src = reseau1.src  
   break;
   case "sortie3" :
 document.e3.src = reseau0.src
       break;
       case "entree4" :
   document.e4.src = contact1.src  
   break;
   case "sortie4" :
 document.e4.src = contact0.src
       break;
       }
}