title: Custom Form validation in CakePHP
body: <p>This is my form: I want to make sure that AT LEAST one of the name/email pairs are filled in, so I'm working on a custom validation rule in my model.</p>
  
  <p><a href="http://files.getdropbox.com/u/240752/formfields.png" rel="nofollow noreferrer">alt text http://files.getdropbox.com/u/240752/formfields.png</a></p>
  
  <p>I originally thought it would a simple case of making the first name/email pair mandatory, but this doesn't cover the other fields if someone fills in the third one for example, and omits the email.</p>
  
  <p>Also, I only need to check for a valid email address if the corresponding friend field is filled in.</p>
  
  <p>Am I overthinking this? I think I need some kind of interaction between the rules, but I'm stuck hard.</p>