title: Magento. Add gender and Date of birthday to registration form
body: <p>I want to put 2 fields on user registration form, /customer/account/create/. Those fields are
  gender selection and day of birth.</p>
  
  <p>As I saw magento's customer module already has those 2 attributes, so If I don't mistake, I don't need to mess up with tables. </p>
  
  <p>So how this can be done? Via observers? Or controller rewrite? What is better option?</p>
  
  <p>My Magento is 1.5.</p>