Unknown UDP port opened by bind ?

[bounce at holiday.home.org]

I'm running bind 8.2.2-p3 with Red Hat Linux 6.0.  When bind is started,
besides TCP and UDP ports on 53, a "netstat -a" shows that bind is
listening on UDP port 1024 ?  Any idea what this is ?

Starting up another instance of bind opens the next consecutive UDP
port (1025).  If I shutdown bind, these ports disappear.

I've looked in the excellent ORA bind book and this newsgroup, but
nothing found.

Thanks in advance.

   - John, bounce at cerebus.demon.co.uk