[c-nsp] SUP-32 and SIP-400

[MKS]

Hello list

I was under the impression that sip-400 required sup-720-3b/3bxl or greater
because the sup-32 doesn't have fabric connectivity.

http://www.cisco.com/en/US/products/hw/routers/ps368/products_data_sheet0900aecd8027c9e6.html

According to this document, only the supervisor Engine 720-3B and 720-3BXL
are listed.
But when I tried sloting sip-400 into a chassis with sup-32 it came up just
fine.
Is this something that has changed recently or has sup-32 always supported
the sup-400.
According to this
http://www-search.cisco.com/univercd/cc/td/doc/product/lan/cat6000/122sx/ol_4164.htm#wp2565000
It's only the sip-600 that isn't supported on sup-32.

What about performance difference between sip-400 with sup32 vs. sup-720 ?

Regards
MKS