dude, a BCM IS a switch - i dont understand why you would connect it to another switch? confuzzuled.
I fitted a BCM a few years ago.
Nortel provided a switch/hub as part of the package.
Nothing abnormal from what i can remember McB. In fact i think we took a switch to site and then realised one was supplied. Plain old run of the mill switch which obviously has the correct amount of ports for the ext's and a bit of future expansion.
I can find out 100% for you in the morning, i will phone one of the guys i work with.
The ext's are just IP addresses so it doesnt matter what switch/hub it is.
It was 2002 though and one of the first BCM's we fitted here.