Using JScript.NET to implement a function

Hello,

I am very familiar with JScript, but not with JScript.NET or C#.  I want 
to write a function in JScript.NET that I can use in my NAnt script.

I currently have:

<project name="TestFunction">

    <target name="go"><echo>${script::testfunc()}</echo></target>
   
    <script language="JS">
        <code>
        <![CDATA[
        public function testfunc():String { return ("Hello World from 
JS"); }
        ]]>
        </code>
    </script>
</project>

But when I run this I get:

C:\hp\Scripts>nant -f:a.build go
NAnt 0.86 (Build 0.86.2898.0; beta1; 12/8/2007)
Copyright (C) 2001-2007 Gerry Shaw
http://nant.sourceforge.net

Buildfile: file:///C:/hp/Scripts/a.build
Target framework: Microsoft .NET Framework 3.5
Target(s) specified: go

   [script] Scanning assembly "l-qhzdpm" for extensions.

go:


BUILD FAILED

C:\hp\Scripts\a.build(4,4):
Unknown function 'script::testfunc'.
Expression: ${script::testfunc()}
              ^^^^^^^^^^^^^^^^^

Total time: 0.4 seconds.

even though it sure looks like I have defined the function "testfunc".  
Anybody have any pointers?

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