Adding documentation to Jars

I am using Eclipse and I want to be able to have the documentation in the jars. 



I followed the isntructions in the "Adding Documentation to the JARs" section of the "Setting up Eclipse to build jME" tutorial, but when I click attach source on a class file and select the jar it is in I get "The source attachment does not contain the source for the file AnimationController.class"  Below contains the bit of code in my build.xml file whcih the tutorial said to change.  I have deleted the jars and rebuilt them, but I get the same thing.



<!-- Compiles all the jME classes, including com.jmex.* -->
   <target name="compile" depends="init" description="generate jme classes">
      <mkdir dir="${class}" />
      <mkdir dir="${class}/com" />
      <copy todir="${class}/com">
         <fileset dir="${src}/com">
            <!-- <exclude name="**/*.java" /> -->
         </fileset>
      </copy>



As the code shows I commented out <exclude name="**/*.java" />