When using a beanshell script, Ant shows a special behavior together with
references.
To have beanshell, I used bsf-2.3.0.jar and bsh-2.0b4.jar in the ${ant.home}/lib
directory.


<?xml version="1.0"?>
<project name="antbug">

  <macrodef name="compileMapper" >
    <attribute name="objDir" />
    <attribute name="id" default="compileMapperID" />
    <sequential>
      <mapper id="@{id}">
        <chainedmapper  >
          <flattenmapper/>
          <globmapper from="*" to="@{objDir}/*.o"/>
        </chainedmapper>
      </mapper>
    </sequential>
  </macrodef>

  <target name="failes">
      <script language="beanshell"><![CDATA[
      // nothing
      ]]></script>
      <!-- throws java.lang.ClassCastException:
org.apache.tools.ant.types.Mapper -->
      <compileMapper objDir="." />
  </target>

  <target name="works">
      <compileMapper objDir="." />
  </target>

  <target name="override" >
      <script language="beanshell"><![CDATA[
      // nothing
      ]]></script>
      <!-- Overriding previous definition of reference to anID -->
      <path id="anID">
        <fileset dir="." includes="*.ant" />
      </path>
  </target>

  <target name="noOverride" >
      <path id="anID">
        <fileset dir="." includes="*.ant" />
      </path>
  </target>

</project>