function check_empty(text) {
  return (text.length > 0); // returns false if empty
}

function check_email(address) {
  if ((address == "")
    || (address.indexOf ('@') == -1)
    || (address.indexOf ('.') == -1))
      return false;
  return true;
}

function check_url(address) {
  if ((address == "")
    || (address.indexOf ('http://') == -1)
    || (address.indexOf ('.') == -1))
      return false;
  return true;
}

// function show
var win = null;
function show(mypage,myname,w,h,scroll){
	LeftPosition = (screen.width) ? (screen.width-w)/2 : 0;
	TopPosition = (screen.height) ? (screen.height-h-50)/2 : 0;
	settings = 'height='+h+',width='+w+',top='+TopPosition+',left='+LeftPosition+',scrollbars='+scroll+',resizable';
	win = window.open(mypage,myname,settings);
	if(win.window.focus)
		{win.window.focus();}
}

function MM_goToURL() { //v3.0
  var i, args=MM_goToURL.arguments; document.MM_returnValue = false;
  for (i=0; i<(args.length-1); i+=2) eval(args[i]+".location='"+args[i+1]+"'");
}