Keeping directory names in jar files

I'm an absolute Ant beginner with a jar task problem. In the past I build my jar files directly in Eclipse, but now I'd like to do the same with Ant. In my project working directory I have 3 subdirectories, which I'd like to add to a single jar file, while keeping the original directory structure.

Directory structure:

D:\FNProg2PDA\config
D:\FNProg2PDA\help
D:\FNProg2PDA\images

Jar-entries as produced by Eclipse Export to Jar file:

META-INF\MANIFEST.mf
config\*.config
help\*.html
images\*.jpg


Jar-entries that Ant however creates, no matter what I try to do:

META-INF\MANIFEST.mf
*.config
*.html
*.jpg

This is what my Ant build.xml looks like:

<?xml version="1.0" encoding="UTF-8"?>

<project name="Builder" default="build"
basedir=".">
<description>
</description>

<target name="build" description="Build the Project jars">
<jar destfile="resources.jar">
<fileset dir="config"/>
<fileset dir="help"/>
<fileset dir="images"/>
</jar>
</target>
</project>

Thanks in advance for your help,

Tom