[c-nsp] 6509 Sup720-3B with 6816-GBIC and DFC

[Sam Munzani]

If you configure Cisco 6509 switch with Sup720-3B with WS-X6816-GBIC and 
try to add WS-F6K-DFC to the GBIC it gives following message

"Two or more selected items are incompatible. Selected or 
default-included item [WS-F6K-DFC] is incompatible with: [WS-SUP720-3B]. 
Please change one or more items.--"

Does anybody know why? Does 720-3B already comes with Distributed 
Forwarding or 720-3B is stripped down so that it can't do DFC at all?

Any idea will be greatly appreciated.

Thanks,
Sam