Deadwood has had in place the ability to filter and remove packets like this, which I set up to be disabled in Deadwood 2.4.08 because sometimes filtering causes these packets causes issues (read this thread for the gory details); however with the particular upstream servers I use, setting it to 0 is better.
So, if you use Deadwood and are having problems with your browser or what not reporting it can’t find sites at times, add the following line to your dwood2rc file:
deliver_all = 0
