Problems building a Windows 2008 Failover cluster

[Thinkpad21]

Whey trying to verify a Windows 2008 failover cluster for an Exchange 2K7
SP1 CCR ( before adding a second node ), I get the following :
Local Area Connection* 9
Adapter Description Teredo Tunneling Pseudo-Interface
Physical Address 02-00-54-55-4E-01-00-00
Status Not Operational
IP Address fe80::100:7f:fffe%12
Prefix Length 64


Found duplicate IP address fe80::100:7f:fffe%12 on node EXCH-CCR-N1.xyz.com
adapter Local Area Connection* 9 and node EXCH-CCR-N2.xyz.com adapter Local
Area Connection* 9.

I have removed IPv6 check mark from both nodes, but still same thing... I
can see that the IP for this adapter is the same, but how would I change
this, and I tought that Teredo Tunneling adapter was only for IPv6, and by
removing IPv6, it would go away...

Just wondering...

Thanks !!!

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