mknod, devfs and FreeBSD

[Freminlins]

Hello,

I have a web server still running FreeBSD 4.7 which I want to update to
FreeBSD 6.2. There are quite a few sites on this machine, and each of them
has a chroot containing their own /dev. In their /dev are things like null,
zero, random and so on.

I don't really want to set up or mount numerous devfs file systems. I tried
creating the the relevent files using mknod but they don't work. What is the
best way to proceed?

Thanks,
Frem.