<?php

# Using Zend 1.11.5

require_once('Zend/Form/Element/Text.php');

$email = new Zend_Form_Element_Text('email');
        $email->setLabel('Email address')
              ->addFilter('StringToLower')
              ->setRequired(true)
              ->addValidator('NotEmpty')
              ->addValidator('EmailAddress');

// Hangs indefinitely unless I remove EmailAddress validator from $email:
var_dump($email->isValid('some_user@blah.ca'));

?>