FYI: there is a problem when upgrading the version of pants to use the new style lock. If you run a new version of pants, it leaves behind a lock file that breaks old versions of pants:

2016-04-02 10:02:26,500: Regenerated BUILD files in 8.718 seconds.
*** Using BETA channel.  Unset SQPANTS_VERSION to use the stable channel.
Running Pants version square-20160329-01
INFO] Detected git repository at /Users/zundel/Development/java on branch zundel/jooq-generate-all-pants
Waiting on pants process None (/usr/local/Cellar/python/2.7.10_2/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python /Users/zundel/.cache/pants/bin/pants/pants-square-20160329-01.pex jooq topsawyer/topsawyer-model:jooq   ) to complete
Exception caught: (<class 'lockfile.AlreadyLocked'>)