title: How to use XSL functions with Xalan?
body: <p>This is my XSL:</p>
  
  <pre><code>&lt;xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:r="my-own-namespace"
    version="2.0" exclude-result-prefixes="xs"&gt;
    &lt;xsl:template match="/"&gt;
      &lt;xsl:value-of select="r:foo('test')"/&gt;
    &lt;/xsl:template&gt;
    &lt;xsl:function name="r:foo"&gt;
      &lt;xsl:value-of select="$val"/&gt;
    &lt;/xsl:function&gt;
  &lt;/xsl:stylesheet&gt;
  </code></pre>
  
  <p>This is what Xalan 2.7.1 (used from Java) is saying:</p>
  
  <pre><code>(Location of error unknown)java.lang.NoSuchMethodException: For extension 
  function, could not find method 
  org.apache.xml.utils.NodeVector.foo([ExpressionContext,] ).
  </code></pre>
  
  <p>What is is about? How to solve the problem?</p>