Suricata

Hi,
Maybe Im find a regression between suricata v0.9.1 and yesterday git (79443b1991840930ded4b8f09ba6de7b000912d9)
ok with this old sig, I have a FP with joigned my (anonymized) pcap file:
alert udp any any -> any 53 (msg:"DNS zone transfer UDP"; content:"|00 00 FC|"; offset:14; classtype:attempted-recon; sid:1948; rev:6;)
alert firing:
04/01/09-14:36:40.894688 [**] [1:1948:6] DNS zone transfer UDP [**] [Classification: ...] [Priority: 3] {1} 10.50.1.143:3 -> 142.27.128.1:3
Joigned pcap file contains 3 packets: first is dns A request, second is dns reply, third is icmp port (dns) unreach (FP hear).
and it's special, because, if you extract only 3ieme packet, no alert!
It's not a fuzzing, it's "normal" dns trafic.
Regards
Rmkml