function ValidateLogin(form)
{
   if(IsEmpty(form.loginname)) 
   { 
      alert('Enter a login name and password to enter') ;
      form.loginname.focus(); 
      return false; 
   } 

   if(IsEmpty(form.loginpassword)) 
   { 
      alert('Enter a login name and password to enter') ;
      form.loginpassword.focus(); 
      return false; 
   } 
}

function IsNumeric(sText)
{
   var ValidChars = "0123456789.";
   var IsNumber=true;
   var Char;

   for (i = 0; i < sText.length && IsNumber == true; i++) 
      { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1) 
         {
         IsNumber = false;
         }
      }
   return IsNumber;
}

function checkMail(sEmail)
{
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	if (filter.test(sEmail)) return true;
}


function IsEmpty(aTextField) {
   if ((aTextField.value.length==0) ||
   (aTextField.value==null)) {
      return true;
   }
   else { return false; }
}