Problem setting part of xpath as parameter

Hi all!

Im having a problem with a parameter set from java to a xsl document.
It used to work. But moving from version Xalan Java 1 to Xalan Java 2  it 
doesnt anymore.

I have the following Java testcode, that makes the transformation:

try {
         String fileName = 
"C:\\javadevelopSource\\Danskkaution8.1\\src\\web\\WEB-INF\\classes\\xsls\\topmenu.xsl";
         String xmlfile= 
"C:\\javadevelopSource\\Danskkaution8.1\\src\\web\\WEB-INF\\classes\\uniklink\\uniklink.xml";
         File file = new File(fileName);
         File file2 = new File(xmlfile);
         StreamSource source = new StreamSource(file);
         TransformerFactory f = TransformerFactory.newInstance();
         Transformer trans = f.newTransformer(source);
          StringWriter out=new StringWriter();
          StreamResult result=new StreamResult(out); 
          trans.setParameter("xpath", "Root[1]/Niv0[1]/Niv1[1]/");
          trans.transform(new StreamSource(file2),result);
          System.out.println(out);
        } catch (Exception e) {
            fail("Error on transforming xml with xsl "+e);
        }

in the xsl file I have the following:
.
.
.
<xsl:param  name="xpath" />
.
.
<xsl:for-each select="$xpath/child::node()[(_at_)Visible='true'].......more 
conditions...

The error I get is:
org.apache.xpath.XPathException: Can not convert #STRING to a NodeList!


Somehow it cant put the value of the xpath parameter in the select 
statement and interpret it as a nodelist.

I can output the value in the xsl by:

<xsl:value-of select="$xpath"/>

giving the String:
Root[1]/Niv0[1]/Niv1[1]/

In xalanJ version 1 I put the value set in java in qoutes (')
 trans.setParameter("xpath", " 'Root[1]/Niv0[1]/Niv1[1]/' ");

and it worked fine. 
This gives an error in version 2 and I read in the documentation, that ' 
no longer was necessary.

Anyway it still doesnt work!

Can anyone give me an explanation and solution?

Thanks in advance!


Lillian Djurhuus