ZCML File
configure.zcml

<configure
    xmlns="http://namespaces.zope.org/zope"
    xmlns:mail="http://namespaces.zope.org/mail"
    i18n_domain="zope"
    >
<permission
    id="zope.SendMail"
    title="[send-mail-permission] Send out mail with arbitrary from and to addresses"
    />
<mail:smtpMailer
    name="smtp"
    hostname="localhost"
    port="25"
    />
<interface
    interface="zope.sendmail.interfaces.IMailDelivery"
    />
<utility
    component=".vocabulary.MailDeliveryNames"
    name="Mail Delivery Names"
    />
</configure>