kernel panic druing cd boot

[laube@ling.uni-potsdam.de]

I just downloaded debian woody isos and tried to install it to a Sparcstation 
20. It is no problem to boot from the CD, but all the time it wants to mount 
the root fs, it tries to mount it via NFS, but that does not work. So it says: 
trying to mount root fs via floppy. But there is no floppy drive attached.
Isn't there any possibility to mount an install system from the cd?
It is the first time that I install a debian and it is also the first time that 
I install a sparc. Please, watch me as a newbie and answer in easy 
understandable sentences. 
Thanks in advance.
Chris