We are currently stuck with an old version of Cocoon 2.2 trunk.
See:
Re: upgrade strategies for our packaged Cocoon
http://marc.info/?t=116969435600001
These are the possibilities:
0) Ensure that the last known working Cocoon can actually be used:
FOR-1015
1) Use the current Cocoon trunk release via Ivy:
FOR-1016
2) Use the head of Cocoon 2.1 branch:
FOR-955
3) Continue the "forrest2" solution.