e)</div>
      Returns a universal-time representing the time after which the <tt>certificate</tt>
      is not valid.  Signals an error if the <tt>certificate</tt> does not have a
      properly formatted time.
    </p>
    <p>
      <div class="def">Function CL+SSL:CERTIFICATE-NOT-BEFORE-TIME (certificate)</div>
      Returns a universal-time representing the time before which the <tt>certificate</tt>
      is not valid.  Signals an error if the <tt>certificate</tt> does not have a
      properly formatte