FreeBSD Security Advisory (FreeBSD-SA-08:06.bind.asc)

The remote host is missing an update to the system as announced in the referenced advisory FreeBSD-SA-08:06.bind.asc
Upgrade your system to the appropriate stable release or security branch dated after the correction date
BIND 9 is an implementation of the Domain Name System (DNS) protocols. The named(8) daemon is an Internet Domain Name Server. DNS requests contain a query id which is used to match a DNS request with the response and to make it harder for anybody but the DNS server which received the request to send a valid response. The BIND DNS implementation does not randomize the UDP source port when doing remote queries, and the query id alone does not provide adequate randomization.