Directory delete question

[Eric . Hardesty]

I've just downloaded Ant and have found it very useful for keeping track of
different
builds, but I was wondering how to delete a number of directories.  I'm
building
buildyyyymmdd.hhmm directories and at some point later I want to be able to
delete
them so I really want something like this
  <target name="cleanall">
    <delete dir="build*" />
  </target>

I looked at FileSets but that seems to only include files, same with include.

Thanks
Eric