Usage of random-id option in scrub for 3.3 and spamd

[calyth <calyth_(_at_)_shaw_(_dot_)_ca>]

First, congratulation for getting 3.3. I immediately get the floppy and 
updated my system.
I was very interested both the random-id option for scrub and the spamd, 
but the documentation was kinda thin.
From the man pages, the random-id option for scrub supposedly applied 
to only "outbound packets that aren't fragmented after the fragment 
reassemble" normalization. Great. But it seems that I could apply the 
random-id option for both scrub in all random-id and scrub out all 
random-id. I'm curious what's the implecation on my NAT/"firewall" box 
using the scrub out all random-id option.
Spamd is suppose to be a fake MTA that generates traffic against 
spammer. How is this supposed to work?
I'd love to see some more details about random-id and spamd.

Calyth