Amigo, asi funciona en cualquier browser:
Código HTML:
function AddRowsToTable()
{
var tbl = document.getElementById('tblSample');
var lastRow = tbl.rows.length;
var row = tbl.insertRow(lastRow);
var cellRight = row.insertCell(0);
cellRight.innerHTML="<input type='text' name='answers[]' id='answers' class='txtBoxStyle3' size='38'><a hre='#' onClick='DeleteRow(this)'> <img src='../Imagen/Examen_gif/del.gif' border='0'></a> <input type='radio' name='correcto' id='correcto'>";
}
Chequea esta funcion por si acaso:
cloneNode().