Password History Retention

[Simper, Brian D]

I want to implement password history on a Linux machine.  It would be nice to remember up to eight passwords so that users have to use a little more creativity in their passwords.  A setting for this appears to be in /etc/pam.d/system-auth but the authconfig command overwrites this when run.  How do you convince authconfig to remember and respect settings inside this?  Or is there a better way to implement password history retention?

Thanks,

Brian Simper