Problème avec cookie

function ScanCookie(variable) 
{ 
 cook=document.cookie; 
 variable+="="; 
 place=cook.indexOf(variable,0); 
 if(place<=-1) return("0"); 
 else 
 { 
  end=cook.indexOf(";",place) 
  if(end<=-1) return(unescape(cook.substring(place+variable.length,cook.length))); 
  else return(unescape(cook.substring(place+variable.length,end))); 
 } 
}