WAL configuration and REINDEX

Hello admins,

 I have a PostgreSQL 8.1.4 server under Linux Red Hat with several
databases. The server is configured with WAL archiving turned on. As a
maintenance process, every night one cron job launches a backup process
to the server with
pg_dump, then the server shuts down and starts up and do a REINDEX
DATABASE to all databases to keep all tables reindexed.

 After 30 days of no activity to the server (this is a DBA test server)
the amount of WAL segments is increasing at very high speed. Every
REINDEX process generates between 25 and 30 WAL segments. With this
behavior (and no activity!!) I can not maintain this amount of data to
performs future WAL backups and recovers.

 Any idea to decrease the number of WAL segments generated?
 Is possible to know when a table would be reindexed and to avoid dayly
REINDEX process?

 Thank you.
 Jose Manuel García V.