duplicate key in unique index pg_statistic_relid_att_index

Hi,

We are running postgres 7.2.

On a regular basis now I am getting duplicate keys in unique index pg_statistic_relid_att_index.  Could this be cause by in insert into a table that is being "vacuum analyse" 'd ?

I have tried reindexing the database, but it always fails because there are duplicate rows in pg_statisitic.  This leads to even more problems because the object for the index in data/base disappears. 

I have checked all my application code.  But inserting while vacuuming is somthing I am not sure about.

The inserts are comming from a client using pg_connect.  A vacuum analyse on certain tables while inserts are being executed is very possible.

I am going to change the code to "vacuum full analyse" in our test regions.  But this is not ideal in our production regions.

Thanks