Hi list,

I found a few related topic around this issue, all referring to the fact that (and
I quote):

Assuming your firewall rules are set up appropriately to allow this traffic, the
reason is because they are duplicate or last packets of a session. This is
explained as follows by the IPFilter howto.

http://m0n0.ch/wall/docbook/faq-legit-traffic-dropped.html

However, I find that some connections do not start at all and get blocked. This is
mainly http traffic and or exchange protocol (sorry, we can't implement a decent
mailserver ;-) ).

Any thought on this ???

-- Jeroen.