wtmp question

[MHR <mray@coral-tech.com>]

I was just browsing through the Linux Security HOWTO for tips on further
securing my new firewall/router when I came across the following.

http://www.linuxdoc.org/HOWTO/Security-HOWTO-5.html
The /var/log/wtmp and /var/run/utmp files contain the login records for
all users on your system. Their integrity must be maintained because
they can be used to determine when and from where a user (or potential
intruder) has entered your system.  These files should also have 644
permissions, without affecting normal system operation. 


Unless something I installed modified it, my /var/log/wtmp was set to
664.  Is there a reason for this?

Thanks,
Matt Ray