Extreme bloating of intarray GiST indexes

Hackers,

I'm currently looking at a database which has some extreme bloating of
intarray GiST indexes.  As in 1000% bloating in only a few months.  This
is not a particularly high-transaction-rate database, so the bloating is
a little surprising; I can only explain it if vacuum wasn't cleaning the
indexes at all, and maybe not even then.

We're currently instrumenting the database so that we can collect a bit
more data on update activity, but in the meantime, has anyone seen
anything like this?

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com