Debian release cycle for enterprise ?

["Frédéric PICA" <frederic.pica@gmail.com>]

Greets,

I am looking on the debian release cycle and I saw that the lenny release is planned for 2008-2009.
I want to use debian in a production environnement and I think this life time is to short.
I need to have a stable distribution for at least 4 years (5 years will be great), and I saw on the debian FAQ that the security team support only one year an oldstable.
I'm sure that a such life cycle will be great for desktop users but what about production servers ?
I could take a DNS server in example, when the server is configured and work, I have no reason to update the server to a new release for at least 4 years if it have the latest security patches. Upgrading to a new stable version means updating configuration files, doing a complete checkup, a test phase, ...

So is it planned to update the duration of security patches for oldstable ? Or is there a solution for my problem ?

Thanks you