function check_email( email_field ) {
  if ( email_field.value.length<3 || !email_field.value.match(/^\w+[\.\-\w]*@(\w+\-*\w*\.)+\w+$/)) 
  {
  	alert ('Ââåäèòå êîððåêòíûé email');
  	email_field.focus();
  	return false;
  }
   
  return true;
}