Alternative to msxsl:node-set function

I have declared the following variable in my stylesheet, and I am using the
msxsl:node-set function to access elements within the variable. Since the
stylesheet must be migrated from MSXML to Xalan, is there another way to
access this variable?
 
Maria
 
 <xsl:variable name="SideNav">
  <SiteNavigationLinks>
   <NavigationLink>
    <LinkName>Homepage</LinkName>
    <IsDisplayed>1</IsDisplayed>
    <LinkText>Home</LinkText>
    <HRef>/framework/homepage/homepage.asp</HRef>
    <AltText>Get the latest news about the webdoxs service.</AltText>
    <ImgSrc>./images/triangle_<xsl:value-of select="$ImgVer"/>.gif</ImgSrc>
    <ImgHiSrc>./images/triangle_<xsl:value-of
select="$ImgVer"/>.gif</ImgHiSrc>
    <ImgWidth>15</ImgWidth>
    <ImgHeight>10</ImgHeight>
   </NavigationLink>
   <NavigationLink>
    <LinkName>Current Activity</LinkName>
    <IsDisplayed>1</IsDisplayed>
    <LinkText>Inbox</LinkText>
    <HRef>/framework/currentbills/currentbills.asp</HRef>
    <AltText>View your last documents received.</AltText>
    <ImgSrc>./images/triangle_<xsl:value-of select="$ImgVer"/>.gif</ImgSrc>
    <ImgHiSrc>./images/triangle_<xsl:value-of
select="$ImgVer"/>.gif</ImgHiSrc>
    <ImgWidth>15</ImgWidth>
    <ImgHeight>10</ImgHeight>
   </NavigationLink>
  </SiteNavigationLinks>
 </xsl:variable>
 
  <xsl:for-each
select="msxsl:node-set($SideNav)/SiteNavigationLinks/NavigationLink">
   <td width="15" valign="top">
    <img>
     <xsl:attribute name="src"><xsl:value-of
select="ImgSrc"/></xsl:attribute>
     <xsl:attribute name="width"><xsl:value-of
select="ImgWidth"/></xsl:attribute>
     <xsl:attribute name="height"><xsl:value-of
select="ImgHeight"/></xsl:attribute>
     <xsl:attribute name="target">_top</xsl:attribute>
    </img>
   </td>
  </xsl:for-each>