Hello,
In some cases dumping flowdata shows "tcpflags" in extended format.
2010-04-12 16:53:44.408 0.000 UDP 192.168.0.1 -> 192.168.0.1.:53 .A.... 0 1 73 0 0 73 1
does this output have any special means? udp itself obviously does not have any "flags".