The site  http://www.packetfactory.net seems to have gone. This 
effects at least two packages:

devel/libnet
net/nemesis

Note that nemesis can now be found at http://jeff.wwti.com/nemesis/

I have no idea where libnet has moved to. If anyone knows could they 
tell me as I'm looking to fetch a more up to date source than the one 
used in pkgsrc.

--Sean