installing 6.0 over the network

I did:
cd /usr/src
make buildworld buildkernel
cd release
make release MYBUILD CHROOTDIR=/usr/tmp/chroot CVSROOT={path to my 
mirror} RELEASETAG=RELENG_6

as the man page states.

this built successfully

then I set my dhcpd parameters to give
a pxeboot address of
/usr/tmp/chroot/R/cdrom/disc1/boot/pxeboot
and
set teh root directory to be
/usr/tmp/chroot/R/cdrom/disc1
(and exported it)

on boot, my netbooting system does in fact boot with an NFS root 
directory running
the correct kernel etc.

however what I want is to make it boot into sysinstall rather than booting
into init..
how do I make is do this?

I did basically hte same thing for 4.11 and it loaded sysinstall.
what do I have to do differently in 6.0 to make this happen?

I did log into the netbooted system and run sysinstall by hand but it 
isn't quite the same..


julian