EXSLT problem - XalanJ 2.5.1

[Everett Stauffer]

Hi folks-

Maybe I'm missing something but I can't seem to get exslt functions
to work with XalanJ 2.5.1.
I've declared the namespace:
  xmlns:set="http://exslt.org/sets";
I'm trying to setup a nodelist with:
  <xsl:variable name="orgs" select="set:distinct(//ORG)"/>
I get the following error:
javax.servlet.ServletException: java.lang.NoSuchMethodException
For extension function, could not find method 
org.apache.xpath.axes.DescendantIterator.distinct([ExpressionContext,] ).

This is on Tomcat 3.2.3, with JDK 1.4.0.

Mind you, I've been using Xalan for a couple of years without any problems.

Just for kicks, I tried something even more brain-dead:

  xmlns:date="http://exslt.org/dates-and-times";

The following:
  <xsl:value-of select="date:dateTime()"/>
produces:
javax.servlet.ServletException: javax.xml.transform.TransformerException: 
Instance method call to method dateTime requires an Object instance as first 
argument

Which is pretty surprising considering that the API docs state:
static java.lang.String         dateTime()
   The date:date-time function returns the current date and time as a
   date/time string.
Soooo, what am I missing in using EXSLT functions?

TIA,

Everett