<?otherwise:?> does not work in header of RTF

I have the following code in the header section of an RTF. 

<?choose:?><?when:$p_BusUnitCode='HGD'?><?call-template:ContractSummaryHGD?><?end when?><?otherwise:?><?call-template:ContractSummaryHSI?><?end otherwise?><?end choose?>

BiPublisher is generating the following in the XSL it generates when it convers this statement.

                <xsl:choose>

                     <xsl:when test="$p_BusUnitCode = 'HGD'">

                        <fo:block orphans="2" linefeed-treatment="preserve" end-indent="5.4pt" start-indent="5.4pt" text-align="start" widows="2" padding-bottom="0.0pt" padding-top="0.0pt">

                           <xsl:call-template name="ContractSummaryHGD">

                              <xsl:with-param name="_XDOFOPOS" select="$_XDOFOPOS"/>

                              <xsl:with-param name="_XDOFOPOS2" select="$_XDOFOPOS2"/>

                              <xsl:with-param name="_XDOFOOSTOTAL" select="$_XDOFOOSTOTAL"/>

                              <xsl:with-param name="_XDOFOTOTAL" select="$_XDOFOTOTAL"/>

                              <xsl:with-param name="_SECTION_NAME" select="$_SECTION_NAME"/>