function markall(id) {
 var j=0;
 var l=id.length-4;
 for (j;j<=l;j++)
   {
    id.elements[j].checked=1;
   }
}

function unmarkall(id) {
 var j=0;
 var l=id.length-5;
 for (j;j<=l;j++)
   {
    id.elements[j].checked=0;
   }
}