no boot after kernel compilation of 2.11BSD

[shadoooo]

Hello.
I installed 2.11BSD on my 11/53 and now I'm trying to add network
support to it.
I copied the GENERIC file in /sys/conf to SYSTEM, and edited the
params for the new system.
I'm using disks connected to RQDX3, so basically my root partition is
on /dev/ra0a and swap in /dev/ra0b.
I changed the rows in SYSTEM accordingly, to use the ra disks instead
of the xp of GENERIC:

PIPEDEV makedev(5,0) # makedev(5,0) ra0a
ROOTDEV makedev(5,0) # makedev(5,0) ra0a
SWAPDEV makedev(5,1) # makedev(5,1) ra0b

then if course I changed other parameters for the DELQA and my
particular system.
I had to change some linking options in the generated Makefile, to fix
the overlay problems, then
linking has been completed, so I installed the new kernel with "make
install". I copied the distribution kernel before, as backup "cp /
unix /genunix".

Then I shutdown the system and rebooted it:
53Boot from ra(0,0,0) at 0172150
: ra(0,0,0)unix
Boot: bootdev=02400 bootcsr=0172150

2.11 BSD UNIX #10: Fri Jun 9 00:57:34 PDT 1995
root@:/usr/src/sys/SYSTEM

panic: jump to 0
no fs on dev 5/0
syncing disks... done

I cannot let the system boot from the disk using the new kernel
(unix).
If I use the old one (genunix) the system boots as always.
I don't understand if the problem is on the makedev(5,0) rows...
Any idea?