[c-nsp] RFC 3623 OSPF Graceful Restart question

[Hank Nussbacher]

I have read over Cisco Nonstop Forwarding with Stateful Switchover 
Deployment Guide:
http://www.cisco.com/en/US/products/ps6550/products_white_paper0900aecd801dc5e2.shtml

I see it states:
"The current standard for OSPF Hitless Restart is RFC 3623 Graceful OSPF 
Restart. Cisco provides a configuration option for support of RFC 3623 or 
for the Cisco draft version. See 
<http://www.cisco.com/en/US/products/sw/iosswrel/ps1829/products_feature_guide09186a00805e8fbd.html>
The current standard for OSPF Hitless Restart is RFC 3623 Graceful OSPF 
Restart. The Cisco implementation is currently (at the time of this 
writing) not interoperable with RFC 3623."

and from:
http://www.cisco.com/en/US/products/sw/iosswrel/ps1829/products_feature_guide09186a00805e8fbd.html
and I see the option "nsf ietf" and I see the versions of IOS that support 
it but is it *fully* compatible to RFC3623 or not?  The Cisco Nonstop 
Forwarding with Stateful Switchover Deployment Guide from Aug 2006 states 
it is not interoperable and RFC4167 gives no support either.

Thanks,
Hank