[gentoo-amd64] Problem with USB-Keyboard at Install

[Gerhard Erker 1]

Hello
I have a Microsoft wireless Laser Keyboard 6000 V2.0 and the Microsoft
wireless Laser Mouse 6000.
I tried to install Gentoo for AMD64 from the minimal installation cd.
Unfortunately, when I booted, my keyboard was not recognized. I tried to
boot with the hardware-option "doscsi", but it worked not. I saw that
the "Num Lock" light is on when I switch on the computer. I can also
write Boot-Options. When booting the gentoo-kernel for installation,
Num-Lock switches off and my keyboard will not work.
My Keyboard works on all Linux- and windows installations. Also I don't
found help in Google.
Can anyone help me?
My configuration:
Intel Quadcore Q6600 2.4GHZ
Two SATA harddisks
Nvidia Geforce 9600 
4 GB Memory

If some of you have questions about configuration ... please let me
know. 

Thanks in advance for your help


Gerhard Erker

p.s.:Excuse my english