Kernel & VMware bridging - Whats the difference?

[Rock Lobster <rocklobster () cheerful com>]

Lately, I've been attempting to setup a GenII honeypot on my laptop with vmware.

I do have a couple of questions that I can't quite work out though.

When I compiled my host o/s kernel I forgot to enable bridging and TUN/TAP support,  which according to the UML linux 
paper I read is required for the brctl package to work.  Now the things is,  because bridging wasnt enabled in my 
kernel intially,  why did the vmware guest o/s get an IP from my dhcp server and manage to sit happily on my network 
without any problem?  

I'm also curious as to why I couldnt just install the brctl package and then have the product of vmnet0 placed into my 
iptables rules accordingly?  Why doesnt vmnet0 show up as another network device when I 'ifconfig -a'

Thanks!