I wrote:
> Eric Malm <emalm(at)pivotal(dot)io> writes:
>> We think this may be related to commit 7b63528,
> Yeah, no doubt. I don't think there's anything wrong with that commit,
> but we'll need to make the citext upgrade script even more of a kluge
> in order to dodge the new restriction.
I've pushed a fix for this, if you need it right away:
http://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=7f7eec89b66947e4098773cf286653b9c4f01c88
That's against HEAD but it's the same in all the back branches.
regards, tom lane