In a recent entry to his blog, Neil Garb shows his method for creating compound elements in a Zend_Form object in your Zend Framework website.

Zend_Form can save you a lot of time. It almost completely abstracts away the most boring and error-prone aspects of developing secure and standards-compliant HTML forms. But one thing it doesn't do out of the box is compound elements, such as three-field dates. In this post I'll show you the easiest way to do this ZF-style.

He goes through the creation of the sample controller, an example of a custom element (the multiple date drop-downs he mentioned) and how to handle the validation in a "Zend Framework way" via an isValid call.