<para>Timezone names may not be specified.</para>
<para>The special expressions
+ <literal>minutely</literal>,
<literal>hourly</literal>, <literal>daily</literal>,
<literal>monthly</literal>, <literal>weekly</literal>,
and <literal>yearly</literal> or
<literal>annually</literal> may be used as calendar
events which refer to
+ <literal>*-*-* *:*:00</literal>,
<literal>*-*-* *:00:00</literal>,
<literal>*-*-* 00:00:00</literal>,
<literal>*-*-01 00:00:00</literal>,