OK, I found the problem: building from git and doing 'make install' don't mix.
$ ls /usr/local/lib/couchdb/erlang/lib/ couch-0.11.0b2f476313-git couch-0.11.0b897427 etap couch-0.11.0b6c1ece91-git couch-0.11.0bd19680d5-git ibrowse-1.5.2 couch-0.11.0b894112 erlang-oauth mochiweb-r113 You get an effectively random version of couchdb libraries. Sorry for the noise (although it would be nice if couchdb could be a bit smarter with its load path)
