How to configure Outlook 2007 using IPV6 in Exchange 2007 SP1?

[Mugen]

Hi,
I need to test IPV6 by sending SMTP and incoming mail (Internally) between
Exchange 2007 SP1 and Outlook 2007 email client. I setup 3 machines. A
Windows 2008 DC, one Exchange 2007 SP1 and one Vista SP1 client. Here is what
I found out so far. I have to enabled both IPV4 and IPV6 on W2K8 DC and W2K8
Exchange 2007 SP1 in order to make everythinig work correctly. And then, I
installed Outlook 2007 and disabled IPV4 (Only IPV6 enabled) on Vista SP1
client. However, When I tried to configure Outlook 2007 and enter the
exchange server host name and user account name, it gave me an error saying
something like Outlook client or exchange server is not online and cannot
complete the process. But it worked right away if I enabled IPV4. I checked
online and it said Outlook 2007 supports IPV6 but I just could not make it
work with Exchange 2007 SP1 if I only have IPV6 enabled on Vista client.
Does anyone know how to make IPV6 works between Outlook 2007 and Exchange
2007 SP1? On the other hand, if I enabled both IPV4 and IPV6 on Vista
machine, is there a way to make sure the SMTP mail is working on IPV6 network
instead of IPV4?

Thanks.
Mugen