verification_overwrite_model.php

/**
 * Validation rules
 *
 * @var array
 */
    public $validate = array(
        'email' => array(
            'email' => array(
                'rule' => 'email',
                'required' => false,
                'allowEmtpy' => true,
                'on' => null,
                'message' => 'メールアドレスの形式が間違っています。',
                'last' => true
            )
        )
    );


/**
 * email validation method
 *
 * A verification rule is overwritten.
 */
    public function email($check, $deep = false, $regex = null)
    {
        foreach ($check as $value) {
            if (empty($value)) {
                return true;
            }
            return Validation::email($value, $deep, $regex);
        }
    }