Upgrade from 4.9 to 5.1

[Dmitry A. Bondareff]

Hello hackers!
Help to understand problem.
I have FreeBSD 4.9 on my box.
# uname -a
FreeBSD wall.ru 4.9-RELEASE-p1 FreeBSD 4.9-RELEASE-p1 #24

I've tried to Upgrade it up to 5.1
# cvsup /etc/cvsupfile
# cd /usr/src
# make buildworld
....................
....................
===> lib/libpam/modules/pam_krb5
rm -f .depend
mkdep -f .depend -a    -I/usr/src/lib/libpam/modules/pam_krb5/../../../../contrib/openpam/i
nclude -I/usr/src/lib/libpam/modules/pam_krb5/../../libpam  /usr/src/lib/libpam/modules/pam
_krb5/pam_krb5.c
*** Error code 1

Stop in /usr/src/lib/libpam/modules/pam_krb5.
*** Error code 1

Stop in /usr/src/lib/libpam/modules.
*** Error code 1

Stop in /usr/src/lib/libpam.
*** Error code 1

Stop in /usr/src.
*** Error code 1

Stop in /usr/src.
*** Error code 1

Stop in /usr/src.
*** Error code 1

Stop in /usr/src.


How to resolve this problem.
Thanks.

Dmitry Bondareff.