function chkLoginFrm(){
  var err = false;
  var errMsg = "";
  var f = document.loginform;
  //var email_txt_chk = f.username.value.search(/^(\w+\.)*\w+@(\w+\.)+\w+$/);
  if (f.username.value == "")
  {
	errMsg=errMsg + 'Please enter your "Username".\n';
	err=true;
  }
  if (f.username.value != '')
  {
    if (!emailCheck(f.username.value))
    {
		errMsg=errMsg + 'Please enter a vaild "Username". (Email address only)\n';
		err=true;
    }
  }
   if (f.userpass.value == "")
  {
		errMsg=errMsg + 'Please enter your "Password".\n';
		err=true;
  }
  else
	{
		if(f.userpass.value.length < 6)
		{
			errMsg=errMsg + 'Your "Password" should be at least 6 characters.\n';
			err=true;
		}
	}

 if (err == false){ f.submit(); }else{ alert(errMsg); }
}



function emailCheck (emailStr) {
  var checkTLD=1;
  var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;
  var emailPat=/^(.+)@(.+)$/;
  var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
  var validChars="\[^\\s" + specialChars + "\]";
  var quotedUser="(\"[^\"]*\")";
  var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
  var atom=validChars + '+';
  var word="(" + atom + "|" + quotedUser + ")";
  var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
  var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
  var matchArray=emailStr.match(emailPat);

  if (matchArray==null) {
    return false;
  }

  var user=matchArray[1];
  var domain=matchArray[2];

  for (i=0; i<user.length; i++) {
    if (user.charCodeAt(i)>127) {
      return false;
    }
  }

  for (i=0; i<domain.length; i++) {
    if (domain.charCodeAt(i)>127) {
      return false;
    }
  }

  if (user.match(userPat)==null) {
    return false;
  }

  var IPArray=domain.match(ipDomainPat);
  if (IPArray!=null) {

    for (var i=1;i<=4;i++) {
     if (IPArray[i]>255) {
       return false;
     }
   }
  return true;
  }
  var atomPat=new RegExp("^" + atom + "$");
  var domArr=domain.split(".");
  var len=domArr.length;

  for (i=0;i<len;i++) {
    if (domArr[i].search(atomPat)==-1) {
      return false;
    }
  }

  if (checkTLD && domArr[domArr.length-1].length!=2 && domArr[domArr.length-1].search(knownDomsPat)==-1) {
    return false;
  }

  if (len<2) {
    return false;
  }
  return true;
}