duplicate key errors when restoring 8.4.0 database dump into 9.1.2

Hello I am trying to migrate a database from 8.4.0 to 9.1.2 on a test server before updating the production server.  When piping the dump file created with pg_dump in psql I am getting duplicate key errors and the primary keys on several large tables do not get created.  I have read all the migration notes and do not see anything specific other than a pg_dump restore is required.  Any clues for me?

Thanks,

culley