[Ltib] how to prevent kernel compilation destroying my custom device files

[Claudia De Bartolomeis]

Hi everybody,
I have a similar problem to the previous one:

I have created two devices files into  rootfs/dev/

mknod ts0 c 13 144
mknod can0 c 91 0

but my kernel compilation doesn't create/leave them into my romfs image.
How could I avoid this?

I tried creating them also in the directory merge/dev
but it doesn't work.

Thanks in advance for any help
Claudia