function addLines(lbl) {
  var str = "" + lbl,
      words = str.split(/(\s+)/);
  for (var i=0,n=0; i<words.length; ++i) {
      n += words[i].length;
      if (n >= 10) {
          words[i] = "\n" + words[i];
          n = 0;
      }
  }
  str = words.join("");
  
  return str;
}
function beforeDrawDataPointLabel( dph, label, icsc )
{
  var newLabel = addLines(label.getCaption().getValue())
  label.getCaption().setValue(newLabel);
}