compiling the GIT version -> duplicate classes

[Helmut Jarausch]

Hi,
when I try to compile the GIT sources I (now) get lots of errors like

     [javac]  
/var/tmp/portage/sci-geosciences/josm-99999/work/josm-99999/src/org/apache/commons/jcs/access/AbstractCacheAccess.java:42:  
error: duplicate class:  
org.apache.commons.jcs.access.AbstractCacheAccess
     [javac] public abstract class AbstractCacheAccess<K, V>

What am I missing?
Please bear in mind that I have next to no knowledge in Java.

Many thanks for a hint,
Helmut