Fatal trap 12

Hello.

Could any kind soul help me?

I'm running FreeBSD 5.x on our production web server since
5.0 was first out last year.. I'm a satisfied user of 5.x.

last thursday I was running:

web.dti.supsi.ch# uname -a
FreeBSD web.dti.supsi.ch 5.2-RELEASE-p1 FreeBSD 5.2-RELEASE-p1 #0: Fri 
Jan 30 19:15:51 CET 2004 
root_at_web.dti.supsi.ch:/usr/obj/usr/src/sys/WEB  i386

I cvsupped as always, when ssl fix was available with:
**********************************************
*default tag=RELENG_5_2
*default host=cvsup2.de.freebsd.org
*default prefix=/usr
*default base=/usr/local/etc/cvsup
*default release=cvs delete use-rel-suffix compress
src-all
doc-all
ports-all tag=.
**********************************************

..., make installworld, mergemaster, bla bla bla..

every thing seemed to go well as usual without a problem..

but then, when rebooted I got:

Fratal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address = 0xff70ff70
fault code            = supervisor read, page not present
instruction pointer   = 0x8:0xc055ccc9
stack pointer         = 0x10:0xe40dfb04
frame pointer         = 0x10:0xe40dfb28
code segment          = base 0x0, limit 0xfffff, type 0x1b
                       = DPL 0, pres 1, def32 1, gran 1
processor eflags      = interrupt enabled, resume, IOPL = 0
current process       = 302 (ifconfig)
trap number           = 12
panic: page fault
cpuid = 0;
boot() called on cpu#0

syncing disks...

That was quite late in the boot process.. in fact was
while configuring the network interface. I could get to
single user mode without problem.. but any time I tried to
go to multiuser I got the the above error.

I did a limited restore:
/boot, /bin, /etc /lib, /libexec, /sbin

that was enough to get the system back to multiuser mode
and running great as usual..

Yet.. I cannot seam to be able to upgrade the system any more..

What should I do? . Any ideas?

If neede I can provide more information.

Thank you.
-- 
               Roberto Nunnari -software engineer-
                mailto:roberto.nunnari_at_supsi.ch
  Scuola Universitaria Professionale della Svizzera Italiana
              Dipartimento Tecnologie Innovative
                   http://www.dti.supsi.ch
  SUPSI-DTI
  Via Cantonale                        tel: +41-91-6108561
  6928 Manno                 """       fax: +41-91-6108570
  Switzerland               (o o)
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