Which version of Xen to use with NetBSD 6.1?

[Erik Fair <fair%netbsd.org@localhost>]

If one has an HP Microserver N40L (AMD Turion II Neo N40L dual core CPU) with 
8GB of RAM, and one intends to run nothing but NetBSD 6.1 (or later) as both 
dom0 and domU, what version of Xen & xentools should one use?

My attempts to install and boot Xen to date have all failed at the same point: 
the NetBSD boot loader loads it all up, Xen starts, gets to "scrubbing memory" 
and then the screen goes blank and I have to power-cycle the machine to get it 
back. VGA console - the system has no RS-232 serial ports - just USB.

/boot.cfg contains:
menu=Boot normally:rndseed /var/db/entropy-file;boot netbsd
#
menu=Boot single user:rndseed /var/db/entropy-file;boot netbsd -s
#
menu=Disable ACPI:rndseed /var/db/entropy-file;boot netbsd -2
#
menu=Disable ACPI and SMP:rndseed /var/db/entropy-file;boot netbsd -12
#
menu=Boot Xen (vga):load /netbsd.dom0 console=pc;multiboot /xen.gz 
dom0_mem=256M console=vga
#
menu=Boot Xen (vga, single user):load /netbsd.dom0 -s console=pc;multiboot 
/xen.gz dom0_mem=256M console=vga
#
menu=Drop to boot prompt:prompt
#
default=1
timeout=10
clear=1

This system runs NetBSD 6.1 on bare metal just fine.

        Erik <fair%netbsd.org@localhost>