Corrupt index

I am experiencing frequent index corruptions (approximately once a
week). I solve the problem by using the REINDEX TABLE command and
rerunning my programs. Does anyone know why I might be experiencing
these problems? Also, is there a way to determine whether an index is
corrupt (other than seeing inconsistencies in the data)?

I am running PostgreSQL 7.3.1 on Red Hat 8.0. I access and modify the
database through Java (using the JDBC driver).

Notice:
The contents of this e-mail including any attachments may contain confidential or privileged information and are to be read solely by the intended recipient(s). If you are not an intended recipient of this e-mail or have received this e-mail in error, please note that any dissemination, distribution, copying or retention of this e-mail without express permission is strictly prohibited. If you believe that you received this e-mail in error, please notify the sender by return e-mail and then delete the message; do not read, save, forward or otherwise preserve or disseminate it.