//Login form validaion script

function check_black(){

     if( document.login.username.value == "" )
     {
          alert("Username field left blank!");
          document.login.username.focus();
          return false;
     }
     if( document.login.password.value == "" )
     {
          alert("Password field left blank!");
          document.login.password.focus();
          return false;
     }
return validate_login('login');
}