I tested ports/net/iscsi-target with /sbin/iscontrol and
Microsoft iSCSI Initiator.

These four boxes are,

1)ports/net/iscsi-target on FreeBSD i386
2)/sbin/iscontrol on FreeBSD i386
3)Microsoft iSCSI Initiator on WinXP i386
4)/sbin/iscontrol on FreeBSD sparc64

iscontrol setting is standard and discovery mode run.
2) and 3) run as normally connect successful.
but, bump errors 4).

ports/net/iscsi-target(i386) say,

pid 1829:iscsi.c:577: ***ERROR*** Bad "Byte 1, bits 2-3": Got 1 expected 0.
pid 1829:target.c:789: ***ERROR*** iscsi_login_cmd_decap() failed
pid 1829:target.c:1148: ***ERROR*** login_command_t() failed
pid 1829:target.c:1268: ***ERROR*** execute_t() failed

How-To-Repeat: # -- iscontrol sparc64 settings -- #
> cat /etc/iscsi.conf
port    = 3260
target0 {
        targetaddress   = 192.168.0.1 # your target IP/hostname
        targetname      = iqn.1994-04.org.netbsd.iscsi-target:target0
}
# -- sparc64 box iscsi.conf over -- #

# -- i386 |sparc64 box iscsi-target settings -- #
> cat /usr/local/etc/iscsi/targets
extent0         /tmp/iscsi-target0      0       1MB
target0                rw      extent0         192.168.0.0/24 # your target network address and/or mask
# -- i386 box targets over -- #

# /usr/local/bin/iscsi-t arget -f /usr/local/etc/iscsi/targets -D

# not fork run debugging