failed upgrade from 5.4-STABLE -> 6

[Jason]

ive got a 5.4 box that im trying to upgrade to 6..
all I did was use the RELENG_6 tag and did make world and I error out at

cc -shared -nostdlib hack.c -o hack.So
rm -f hack.c
MAKE=/usr/obj/usr/src/make.sparc64/make sh /usr/src/sys/conf/newvers.sh GENERIC
cc -c -O2 -pipe -fno-strict-aliasing  -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes  
-Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual  -fformat-extensions -std=c99  -nostdinc -I-  -I. 
-I/usr/src/sys -I/usr/src/sys/contrib/altq -I/usr/src/sys/contrib/ipfilter -I/usr/src/sys/contrib/pf 
-I/usr/src/sys/contrib/dev/ath -I/usr/src/sys/contrib/dev/ath/freebsd -I/usr/src/sys/contrib/ngatm 
-I/usr/src/sys/dev/twa -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h -fno-common 
-finline-limit=15000 --param inline-unit-growth=100 --param large-function-growth=1000  -mcmodel=medlow 
-msoft-float -ffreestanding -Werror  vers.c
linking kernel
zs.o(.text+0x488): In function `zstty_attach':
: undefined reference to `zstty_console'
zs.o(.text+0x103c): In function `zstty_param':
: undefined reference to `zstty_set_speed'
*** Error code 1

Stop in /usr/obj/usr/src/sys/SHONUFF.
*** Error code 1

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

Stop in /usr/src.
shonuff# pwd
/usr/src
shonuff#


shonuff# grep RELENG /usr/src/stable-supfile 
#  2.2-stable, change to "RELENG_4", "RELENG_3", or "RELENG_2_2" respectively.
*default release=cvs tag=RELENG_6
shonuff# 


shonuff# uname -a
FreeBSD shonuff.cisco.com 5.4-STABLE FreeBSD 5.4-STABLE #1: Wed May  4 01:45:43 UTC 2005     
jason at shonuff.cisco.com:/usr/obj/usr/src/sys/SHONUFF  sparc64
shonuff# 


please advise,

Jason