the output directory for chunks. (If not specified, the output directory
is system dependent.)</para>
+<para>Starting with version 1.77 of the stylesheets,
+the param's value will have a trailing slash added if it does
+not already have one.</para>
+
+<caution><para>Do not use <parameter>base.dir</parameter>
+to add a filename prefix string to chunked files.
+Instead, use the <parameter>chunked.filename.prefix</parameter>
+parameter.</para></caution>
+
</refsection>
</refentry>