Instructions on how to upgrade findbugs.

Obtain the most recent version of findbugs from:
   http://sourceforge.net/projects/findbugs

Unzip the file into this directory.

In the new directory:
Ensure that plugin contains noUpdateChecks.jar. If it is in optionalPlugin, move copy it from there.
Remove the following:
   bin
   doc
   src
   optionalPlugin

Change the references to the old directory to the new directory in the following files:
   build.xml

In SVN remove the old findbugs directory.