xenU install fails on newfs.

[Glen Johnson <gjohnson%valcom.com@localhost>]

NetBSD-users,
I have Xen0 - NetBSD 5.0.1 running fine.  When I attempt to install a
XenU - NetBSD 5.0.1 I keep running into issues.  Just before the install
screen from sysinst is displayed a message xbd  IO domain 1: error 22
appears in the messages scrolling by.  Then the sysinst menu pops up and
everything appears to run fine until it comes time for newfs to do its
job and I get "wtfs: write error for sector 32: Rad-only file system".

Here is some background info on how I set things up.
The file system that XenU is supposed to use was generated by "dd
if=/dev/zero of=netbsd.img -bs=1024 count=2048 ; chmod 777 netbsd.img". 

My config file for my XenU is /usr/pkg/etc/xen/netbsd1:
kernel = "/usr/pkg/etc/xen/kernels/netbsd-INSTALL_XEN3_DOMU.gz"
memory = 64
name = "netbsd1"
vif = [ 'mac=00:16:3e:00:00:11, bridge=bridge0' ]
disk = [ 'file:/home/glen/img/netbsd.img,3,w','phy:/dev/cd0a,0x4,r' ]
extra = ""
root = "xbd0"



My ifconfig -a shows:
fxp0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
        address: 00:0b:cd:be:10:7f
        media: Ethernet autoselect (100baseTX
full-duplex,flowcontrol,rxpause,txpause)
        status: active
        inet 192.168.45.154 netmask 0xffffff00 broadcast 192.168.45.255
        inet6 fe80::20b:cdff:febe:107f%fxp0 prefixlen 64 scopeid 0x1
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 33192
        inet 127.0.0.1 netmask 0xff000000
        inet6 ::1 prefixlen 128
        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x2
bridge0: flags=41<UP,RUNNING> mtu 1500
xvif1.0:
flags=8963<UP,BROADCAST,NOTRAILERS,RUNNING,PROMISC,SIMPLEX,MULTICAST>
mtu 1500
        capabilities=2800<TCP4CSUM_Tx,UDP4CSUM_Tx>
        enabled=0
        address: 00:16:3e:01:00:11
        inet6 fe80::216:3eff:fe01:11%xvif1.0 prefixlen 64 scopeid 0x4


Questions:
What am I missing?
How do I make the file system not read only?
Is there a problem with my configuration?
Do you need more info?

Thank you for all help,
Glen Johnson