function trapCtrlKeyCombination(e)
{
	var badCtrlKeys = new Array('b','l','n','s','p','e','i','h','a','c','x','v','j','f','o','d');
	var badShiftKeys = new Array(121,115);
	
	var allowKey=true;
  var isCtrl;
  var isShift;
  var isAlt;
  var key;
  if(window.event) // IE
  {
		key = window.event.keyCode; 
		isCtrl = (window.event.ctrlKey)  ? true : false;
		isShift= (window.event.shiftKey) ? true : false;
		isAlt  = (window.event.altKey)   ? true : false;
	}
  else // firefox
  {
    key = e.which;
		isCtrl = (e.ctrlKey)  ? true : false;
		isShift= (e.shiftKey) ? true : false;
		isAlt  = (e.altKey)   ? true : false;
  }
  if(isCtrl)
  {
    for(var i=0; i<badCtrlKeys.length && allowKey; i++)          
      if(badCtrlKeys[i].toLowerCase() == String.fromCharCode(key).toLowerCase())
				allowKey = false;
  }
  if(isShift)
	{
		for(var i=0; i<=badShiftKeys.length && allowKey; i++)
      if(badShiftKeys[i] == key)
				allowKey = false;
	}
	
	if(false == allowKey)
	{
		if(window.event) // IE
		{
			window.event.keyCode = 0;
			window.event.cancelBubble = true;
		}
		else
		{
			e.which = 0;
			e.stopPropagation(); 
		}					
	}
  return allowKey;
}