Thanks for reporting this has been updated, and seems to be in master. If it doesn’t update for you could you please check via $ brew edit libcouchbase to see if you have the newest version pulled? It should point to 2.3.0
class Libcouchbase < Formula
homepage 'http://couchbase.com/communities/c'
url 'http://packages.couchbase.com/clients/c/libcouchbase-2.3.0.tar.gz'
sha1 'dbb97594582e5a9240fa8090bb756990f2d1b550'
...
end
The commands above come from Couchbase documentation. I only use Homebrew to install libcouchbase. Hence, I do not know the other commands and do not have the time or need to learn them. You may wish to modestly expand your installation instructions for libcouchbase to include this upgrade case. One way to save your firm support cash is to edit-in the common problems into your documentation.