xorg core dumped with multi-display setting

hello, friends
wanna to setting multi-display on my Nvidia Quadro FX1400 dual-heads card
and got dumped core... and help??

my xorg.conf

Section "ServerLayout"
Identifier "X.org Configured"
Screen "Screen0" LeftOf "Screen1"
Screen "Screen1" RightOf "Screen0"
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection

Section "Files"
RgbPath "/usr/local/share/X11/rgb"
ModulePath "/usr/local/lib/xorg/modules"
FontPath "/usr/local/lib/X11/fonts/misc/"
FontPath "/usr/local/lib/X11/fonts/TTF/"
FontPath "/usr/local/lib/X11/fonts/OTF"
FontPath "/usr/local/lib/X11/fonts/Type1/"
FontPath "/usr/local/lib/X11/fonts/100dpi/"
FontPath "/usr/local/lib/X11/fonts/75dpi/"
EndSection

Section "Module"
Load "extmod"
Load "record"
Load "dbe"
Load "glx"
Load "GLcore"
Load "xtrap"
Load "dri"
Load "freetype"
Load "type1"
EndSection

Section "InputDevice"
Identifier "Keyboard0"
Driver "kbd"
EndSection

Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/sysmouse"
Option "ZAxisMapping" "4 5 6 7"
EndSection

Section "Monitor"
#DisplaySize 520 330 # mm
Identifier "Monitor0"
VendorName "DEL"
ModelName "DELL 2405FPW"
### Comment all HorizSync and VertRefresh values to use DDC:
HorizSync 30.0 - 81.0
VertRefresh 56.0 - 76.0
Option "DPMS"
EndSection

Section "Monitor"
#DisplaySize 520 330 # mm
Identifier "Monitor1"
VendorName "DEL"
ModelName "DELL 2405FPW"
### Comment all HorizSync and VertRefresh values to use DDC:
HorizSync 30.0 - 81.0
VertRefresh 56.0 - 76.0
Option "DPMS"
EndSection

Section "Device"
### Available Driver options are:-
### Values: <i>: integer, <f>: float, <bool>: "True"/"False",
### <string>: "String", <freq>: "<f> Hz/kHz/MHz"
### [arg]: arg optional
#Option "SWcursor" # [<bool>]
#Option "HWcursor" # [<bool>]
#Option "NoAccel" # [<bool>]
#Option "ShadowFB" # [<bool>]
#Option "UseFBDev" # [<bool>]
#Option "Rotate" # [<str>]
#Option "VideoKey" # <i>
#Option "FlatPanel" # [<bool>]
#Option "FPDither" # [<bool>]
#Option "CrtcNumber" # <i>
#Option "FPScale" # [<bool>]
#Option "FPTweak" # <i>
#Option "DualHead" # [<bool>]
Identifier "Card0"
Driver "nv"
VendorName "nVidia Corporation"
BoardName "NV41GL [Quadro FX 1400]"
BusID "PCI:5:0:0"
EndSection

Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 24
EndSubSection
EndSection

Section "Screen"
Identifier "Screen1"
Device "Card0"
Monitor "Monitor1"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 24
EndSubSection
EndSection


# X -config xorg.conf.multi

X.Org X Server 1.4.0
Release Date: 5 September 2007
X Protocol Version 11, Revision 0
Build Operating System: FreeBSD 7.0-PRERELEASE amd64
Current Operating System: FreeBSD iseasa.gddsn.org.cn 7.0-PRERELEASE
FreeBSD 7.0-PRERELEASE #0: Fri Jan 11 02:33:37 CST 2008
root_at_iseasa.gddsn.org.cn:/usr/obj/usr/src/sys/IBM01 amd64
Build Date: 11 January 2008 04:35:47AM

Before reporting problems, check http://wiki.x.org
to make sure that you have the latest version.
Module Loader present
Markers: (--) probed, (**) from config file, (==) default setting,
(++) from command line, (!!) notice, (II) informational,
(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Wed Jan 16 17:26:47 2008
(++) Using config file: "xorg.conf.multi"
(WW) NV: More than one matching Device section for instances
(BusID: PCI:5:0:0) found: Card0
(II) Module "i2c" already built-in
(II) Module "ddc" already built-in
(II) Module "ramdac" already built-in

Fatal server error:
Caught signal 10. Server aborting

Abort (core dumped)

#gdb -c Xorg.core /usr/local/bin/X
GNU gdb 6.1.1 [FreeBSD]
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "amd64-marcel-freebsd"...(no debugging
symbols found)...

warning: core file may not match specified executable file.
Core was generated by `Xorg'.
Program terminated with signal 6, Aborted.
Reading symbols from /usr/local/lib/libXfont.so.1...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/libXfont.so.1
Reading symbols from /usr/local/lib/libfreetype.so.9...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/libfreetype.so.9
Reading symbols from /usr/local/lib/libXau.so.6...(no debugging symbols
found)...done.
Loaded symbols for /usr/local/lib/libXau.so.6
Reading symbols from /usr/local/lib/libfontenc.so.1...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/libfontenc.so.1
Reading symbols from /lib/libz.so.4...(no debugging symbols found)...done.
Loaded symbols for /lib/libz.so.4
Reading symbols from /usr/local/lib/libpixman-1.so.9...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/libpixman-1.so.9
Reading symbols from /usr/local/lib/libhal.so.1...(no debugging symbols
found)...done.
Loaded symbols for /usr/local/lib/libhal.so.1
Reading symbols from /usr/local/lib/libintl.so.8...(no debugging symbols
found)...done.
Loaded symbols for /usr/local/lib/libintl.so.8
Reading symbols from /usr/local/lib/libiconv.so.3...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/libiconv.so.3
Reading symbols from /usr/local/lib/libdbus-1.so.3...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/libdbus-1.so.3
Reading symbols from /usr/local/lib/libXdmcp.so.6...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/libXdmcp.so.6
Reading symbols from /usr/lib/librpcsvc.so.4...(no debugging symbols
found)...done.
Loaded symbols for /usr/lib/librpcsvc.so.4
Reading symbols from /lib/libm.so.5...(no debugging symbols found)...done.
Loaded symbols for /lib/libm.so.5
Reading symbols from /lib/libc.so.7...(no debugging symbols found)...done.
Loaded symbols for /lib/libc.so.7
Reading symbols from /usr/local/lib/xorg/modules//libpcidata.so...(no
debugging symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules//libpcidata.so
Reading symbols from
/usr/local/lib/xorg/modules/extensions//libextmod.so...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/extensions//libextmod.so
Reading symbols from
/usr/local/lib/xorg/modules/extensions//librecord.so...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/extensions//librecord.so
Reading symbols from
/usr/local/lib/xorg/modules/extensions//libdbe.so...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/extensions//libdbe.so
Reading symbols from
/usr/local/lib/xorg/modules/extensions//libglx.so...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/extensions//libglx.so
Reading symbols from
/usr/local/lib/xorg/modules/extensions//libxtrap.so...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/extensions//libxtrap.so
Reading symbols from
/usr/local/lib/xorg/modules/extensions//libdri.so...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/extensions//libdri.so
Reading symbols from /usr/local/lib/libdrm.so.2...(no debugging symbols
found)...done.
Loaded symbols for /usr/local/lib/libdrm.so.2
Reading symbols from
/usr/local/lib/xorg/modules/fonts//libfreetype.so...(no debugging
symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/fonts//libfreetype.so
Reading symbols from
/usr/local/lib/xorg/modules/fonts//libtype1.so...(no debugging symbols
found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/fonts//libtype1.so
Reading symbols from
/usr/local/lib/xorg/modules/drivers//nv_drv.so...(no debugging symbols
found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/drivers//nv_drv.so
Reading symbols from
/usr/local/lib/xorg/modules/input//mouse_drv.so...(no debugging symbols
found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/input//mouse_drv.so
Reading symbols from /usr/local/lib/xorg/modules/input//kbd_drv.so...(no
debugging symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules/input//kbd_drv.so
Reading symbols from /usr/local/lib/xorg/modules//libint10.so...(no
debugging symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules//libint10.so
Reading symbols from /usr/local/lib/xorg/modules//libvgahw.so...(no
debugging symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules//libvgahw.so
Reading symbols from /usr/local/lib/xorg/modules//libfb.so...(no
debugging symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules//libfb.so
Reading symbols from /usr/local/lib/xorg/modules//libxaa.so...(no
debugging symbols found)...done.
Loaded symbols for /usr/local/lib/xorg/modules//libxaa.so
Reading symbols from /libexec/ld-elf.so.1...(no debugging symbols
found)...done.
Loaded symbols for /libexec/ld-elf.so.1
#0 0x00000008018359dc in kill () from /lib/libc.so.7