var scrolltimer;  
    function initScroll(BlockId, speedScroll, pxIncrement, TimeOver, incrementOver) {  
       var MonObjet = document.getElementById(BlockId);  

         var topDiv = MonObjet.insertBefore(document.createElement("DIV"),MonObjet.firstChild);  
          topDiv.style.height = MonObjet.clientHeight + "px";  
          var bottomDiv = MonObjet.appendChild(document.createElement("DIV"));  
          bottomDiv.style.height = MonObjet.clientHeight + "px";  

          scrollBlock(BlockId, TimeOver, incrementOver, incrementOver); 
        }  
        
        function scrollBlock(BlockId,TimeScroll,pxIncrement){  
           var monObjet = document.getElementById(BlockId)  
            if (TimeScroll=='' | TimeScroll==null | TimeScroll <= 0) TimeScroll = 40;  
            if (pxIncrement=='' | pxIncrement==null | pxIncrement <= 0) pxIncrement = 1;  
            //ScrollTop = ScrollTop + speed;  
            monObjet.scrollTop = monObjet.scrollTop + pxIncrement;  
             if (monObjet.scrollTop >= monObjet.scrollHeight-monObjet.clientHeight) monObjet.scrollTop = 1;  
            scrolltimer = setTimeout("scrollBlock('"+ BlockId + "'," + TimeScroll + "," + pxIncrement +")", TimeScroll);  
        }  
      window.onload = function(){  
            initScroll('bloc_actu',10, 1, 40, 0);  
        }