Another more challenging xslt question for me, i'm trying to relate jobs to country pages (under Network)

I need to list all children of "jobs" on the country pages (under network), if their "relatedCountry" matches $currentpage/id

I was thinking along these lines, but got stuck:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp "&#x00A0;"> ]>
<xsl:stylesheet
  version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:msxml="urn:schemas-microsoft-com:xslt"
  xmlns:umbraco.library="urn:umbraco.library" xmlns:Exslt.ExsltCommon="urn:Exslt.ExsltCommon" xmlns:Exslt.ExsltDatesAndTimes="urn:Exslt.ExsltDatesAndTimes" xmlns:Exslt.ExsltMath="urn:Exslt.ExsltMath" xmlns:Exslt.ExsltRegularExpressions="urn:Exslt.ExsltRegularExpressions" xmlns:Exslt.ExsltStrings="urn:Exslt.ExsltStrings" xmlns:Exslt.ExsltSets="urn:Exslt.ExsltSets"
  exclude-result-prefixes="msxml
 umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes 
Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings 
Exslt.ExsltSets ">

<xsl:output method="xml" omit-xml-declaration="yes" />

<xsl:param name="currentPage"/>

<!-- 'source' of the children to list -->
<xsl:variable name="source" select="/macro/source"/>

<xsl:template match="/">

<xsl:choose>

<!-- Here i need to test if the children of $source/children/@ultimatepickerid match $currentpage/@id-->

<xsl:when test="count(umbraco.library:GetXmlNodeById($source)/* [@isDoc]) &gt; 0">    
<ul>
<xsl:for-each select="umbraco.library:GetXmlNodeById($source)/* [@isDoc and string(umbracoNaviHide) != '1']">
  <li>
    <a href="{umbraco.library:NiceUrl(@id)}">
      <xsl:value-of select="@nodeName"/>
    </a>
  </li>
</xsl:for-each>
</ul>
</xsl:when>
<xsl:otherwise>
    <li>
      <li>
        There are currently no job openings in <xsl:value-of select="relatedCountry"/>. <a href="/en/jobs">Browse all jobs</a>.
  </li>
  </li>
</xsl:otherwise>
</xsl:choose>  
  
</xsl:template>
</xsl:stylesheet>

Can anyone give an example of how to match this? I need to do it in the choose statement because i want to eliminate the empty UL element if there are no matches, and give alternative out ("there are currently no jobs...")