Num Lock Turns off during boot

I have 3 different systems that are Windows NT and when the OS starts up it turns the Num Lock off.
I have BIOS set to turn it on and it does and remains on until NT hits the inital logon screen, then it shuts off.
What I would like to know is there any way to fix this? I would like it to be on.
Is this a registry setting and if so where??

Thanks,

Jeffrey A. Grant
Information Systems