Session section misconfiguration?

[Francesco Cristofori]

Hi all,
I'm a newbie on with radius in general and freeradius and this is my first post on this list, so please be patient, I apologize if my questions are silly.  :-)

I'm trying to understand a freeradius 1.0.0 + mysql 3.23.45 installation (solaris8) someone else made some years ago: in radiusd.conf i have this section:

session {
        radutmp
        sql
}

I believe it's not a wise choice to make double session accounting, so I was thinking to remove the radutmp statement. Is it a good idea? What happens if I leave everything untouched (no radutmp statement removal)?

Thanks in advance,
Francesco.