      <para>The option 'datum="datum name"' can be used to override
the default of NAD27 ("N. America 1927 mean") which is correct for the
continental U.S.</para> <para>Any legal <link linkend="Datums">datum supported
by GPSBabel</link> may be used.  For example, points in Hawaii should
use "Old Hawaiian_mean".</para>
