function verifyPoll(oPoll) {
  //verify at least one response checked ... 
  var cElem=oPoll.elements; 
  var sQuest=cElem[0].name; 
  elem:
  for (var e=0;e<cElem.length;e++) {
    if(cElem[e].type=="radio") {
      var cResps=oPoll[cElem[e].name];
      var bPoll=false;
      resp:
      for(var r=0;r<cResps.length;r++) {
        if(cResps[r].checked) {
          bPoll=true;
          continue elem;
        }
      } 
    }
  }
  if (bPoll) {
    //open window ... 
    var wPoll=window.open('about:blank','pollWindow','top=36,left=36,width=650,height=300,resizable=yes,scrollbars=yes');
    wPoll.focus();
    //set target
    oPoll.target="pollWindow";
    return true;
  } else {
    alert("Merci de répondre à toutes les questions.");
    return false;
  }
}