How to find version of reallu old Debian machine?

[stan]

I've got a really old version of Debian running on an internal amchine. As
a matter offact the kerrnel was last compiled in 2003!

I want to try to find a pacjage (.deb) to install on this machine, and I
need to know the version of Debian on this machine to start googling.

How do I determine this?

-- 
One of the main causes of the fall of the roman empire was that, lacking
zero, they had no way to indicate successful termination of their C
programs.