Need to Downgrade from NIS 2009 to NIS 2008

I installed NIS 2009, but have since found out that one of the city VPNs I use to do work for a client will not support NIS 2009 -- only 2008. (When I had trouble connecting after installing NIS 2009, they said I'd have to downgrade.) Where can I find NIS 2008 online so I can roll back to that previous version.

 

Thanks,

C. Mazenko