function testKeyEvent(event, keyCode)
{
    var match = false;
  
    if (window.event)
    {
        if (window.event.keyCode == keyCode)
        {
            match = true;
        }
    }
    else if (event)
    {
	    if (event.which == keyCode)
	    {
	        match = true;
	    }
    }
  
  return match;
}

function autoTabIfFull(thisField, nextField, event)
{
    if (testKeyEvent(event, 9) || testKeyEvent(event, 16))
    {
        return;
    }
    if (thisField && nextField &&
        thisField.value.length == thisField.maxLength)
    {
        if (nextField.focus)
        {
	        nextField.focus();
	        if (nextField.type == "text")
	        {
	            nextField.select();
	        }
        }
    }
}