alternative anti-spoof 

git-svn-id: http://svn.vuze.com/public/client/trunk@40193 c2c1b7af-1477-405b-86ee-8aefd1fc4dd2
abstracted bloom filter key

git-svn-id: http://svn.vuze.com/public/client/trunk@40194 c2c1b7af-1477-405b-86ee-8aefd1fc4dd2
avoid NPE

git-svn-id: http://svn.vuze.com/public/client/trunk@40195 c2c1b7af-1477-405b-86ee-8aefd1fc4dd2