When libvirt would start dnsmasq?

Hi guys. Under what circumstances libvrirt would start _dnsmasq_ on it's own? I certainly did not plan for libvirt to manage dhcp but sometimes I find: -> $ netstat -utapn | grep \:67 udp        0      0 0.0.0.0:67              0.0.0.0:*              19678/dnsmasq -> $ ps -Fp 19678 UID          PID    PPID  C    SZ   RSS PSR STIME TTY TIME CMD dnsmasq    19678       1  0  2258  1824   8 Oct07 ? 00:00:00 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper which... does fcuk up my main (should be the only) DHCP server. Is it possible to tell libvirt not to do that no matter the circumstances? (or it's not libvirt?) many thanks, L.