Some questions regarding 7.2 systems

I have a receiver which can support 7.2 That being said; I was wondering if there was any way to hook up the sub from my old z5500 as a secondary sub to the system, or if this is even reccomended? I'd be fine simply duplicating the signal from the primary sub, but given the strange connections on the sub I'm not sure if this is even doable.

/Sorry for my incompetence at all this.

it can be done. is the reciever a true 7.2 or does it just have dual sub outputs? a true 7.2 is basically stereo for LFE. MOST implementations are just a extra output, same thing as a y splitter. that said, if it is a real deal 7.2 than having different subs on each channel will probably sound wonky. if its just the extra output route than itd be just like adding the sub to the room, smoother bass response, more volume, etc.

what are these strange connections on the sub that u speak of?

It's like, a 12 pin connecter? I can't explain it properly, it's been a year since I last hooked up the system, but it connects the sub to the receiver.

http://www.theinquirer.net/img/6686/logitech_z-5500_01.jpg

Sadly the best picture I could find; but that big chunky cable underneath the normal audio cables is the one I'm talking about.