Packaging error on WSClient plugin (groovyws-standalone-0.5.0.jar)

Hi folks,

i've played around with the wsclient plugin. It works fine till I tried
"griffon run-applet". That gave me the following error:
----------snip-------------------
[signjar] jarsigner: unable to sign jar: java.util.zip.ZipException:
duplicate entry: META-INF/LICENSE
----------snip--------------------

Looking at groovyws-standalone-0.5.0.jar in the staging directory indeed
gives multiple entries for LICENSE, DEPENDENCIES, LICENSE.txt, NOTICE
and NOTICE.txt in the META-INF directory. The files have different dates
and sizes.
Look like a packaging error.

Cheers,
Jens