マルチカメラアングル機能の黒い枠発生

V1.9.0 でも現象を確認していたのですが、v1.9.1bにバージョンアップしてもサブウィンドウの周囲に520x520ピクセルの黒枠が発生してしまいます。

http://flightgear.jpn.org/uploads/photos/113.jpg

FUJITSU FMV-DESKPOWER CE70E7
CPU　　　　　　:Intel(R)Pentium(R)4 CPU 2.60GHz
RAM　　　　　　:0.99GB
Windows XP Home Edition Version 2002 Sevice Pack2
INTEL(R) EXTREME GRAPHICS 2　Driver Version:6.14.10.4396

起動オプション
----------------------------------------------------------
C:\relax\FlightGear(1.9.1b)\bin\Win32\fgfs.exe
--fg-root=C:\relax\FlightGear(1.9.1b)\data
--fg-scenery=C:\relax\FlightGear(1.9.1b)\data\Scenery;C:\relax\FlightGear(1.9.1b)\scenery;C:\relax\FlightGear(1.9.1b)\terrasync
--airport=RJTT
--runway=34R
--aircraft=c172p
--control=joystick
--config=C:/relax/FlightGear(1.9.1b)/data/multi-hdtv.xml
--disable-intro-music
--disable-random-objects
--prop:/sim/rendering/random-vegetation=false
--disable-panel
--enable-hud
--disable-anti-alias-hud
--disable-hud-3d
--enable-horizon-effect
--enable-enhanced-lighting
--disable-specular-highlight
--enable-ai-models
--fog-fastest
--geometry=1280x512
--visibility=10000
--bpp=32
--timeofday=noon
--atlas=socket,out,5,localhost,5505,udp
--callsign=zero62b
--multiplay=out,10,mpserver01.flightgear.org,5000
--multiplay=in,10,FMV,5000
--generic=file,out,10,fltrec.csv,playbackEx
--prop:/sim/rendering/camera-group/near-field=0
----------------------------------------------------------

コンソール表示
--------------------------------------------------------------
Model Author: Unknown
Creation Date: 2002-01-01
Version: $Id: c172p.xml,v 1.20 2008/09/01 15:14:33 torsten Exp $
Description: Cessna C-172
KI266 dme indicator #0 initialized
Chat [*FGMS*] Welcome to mpserver01 - Berlin, Germany
Chat [*FGMS*] this is version v0.9.11 (LazyRelay enabled)
Chat [*FGMS*] using protocol version v1.1This server is tracked.
Chat [*FGMS*] zero62b is now online, using
Chat [*FGMS*] Aircraft/c172p/Models/c172p.xml
Initializing Nasal Electrical System
Use of <global> in material animation is no longer supported
Use of <global> in material animation is no longer supported
Use of <global> in material animation is no longer supported
Use of <global> in material animation is no longer supported
Use of <global> in material animation is no longer supported
Could not find at least one of the following objects for animation:

antenna-base

Use of <global> in material animation is no longer supported
Could not find at least one of the following objects for animation:

antenna-base

Chat [*FGMS*] Welcome to mpserver01 - Berlin, Germany
Chat [*FGMS*] this is version v0.9.11 (LazyRelay enabled)
Chat [*FGMS*] using protocol version v1.1This server is tracked.
Chat [*FGMS*] zero62b is now online, using
Chat [*FGMS*] Aircraft/c172p/Models/c172p.xml
Chat [*FGMS*] Gooney is now online, using
Chat [*FGMS*] Aircraft/bo105/Models/bo105.xml
power up
Chat [*FGMS*] jaques is now online, using
Chat [*FGMS*] Aircraft/T37/Models/t37.xml
Chat [*FGMS*] client 'mpdummy' has left
Chat [*FGMS*] mpdummy is now online, using
Chat [*FGMS*] Aircraft/c172p/Models/c172p.xml
--------------------------------------------------------------

マルチカメラアングルの定義ファイル
--------------------------------------------------------------
<PropertyList>
<sim>
<rendering>
<camera-group>
<window>
<name>HDTV</name>
<host-name type="string"></host-name>
<display>0</display>
<screen>0</screen>
<width>1280</width>
<height>640</height>
<x>0</x>
<y>0</y>
<decoration type = "bool">false</decoration>
</window>

<!-- HDTV pane 0 - Cockpit view -->
<camera>
<window>
<name>HDTV</name>
</window>
<viewport>
<x>0</x>
<y>0</y>
<width>1280</width>
<height>640</height>
</viewport>
<view>
<heading-deg type = "double">0</heading-deg>
<pitch-deg>-16</pitch-deg>
</view>
<frustum>
<top>0.2350</top>
<bottom>-0.1131</bottom>
<left>-0.2000</left>
<right>0.2000</right>
<near>0.15</near>
<far>120000.0</far>
</frustum>
</camera>

<!-- HDTV pane 1 - Gear view -->
<camera>
<window>
<name type="string">HDTV</name>
</window>
<viewport>
<x>0</x>
<y>240</y>
<width>320</width>
<height>240</height>
</viewport>
<view>
<heading-deg type = "double">0</heading-deg>
<x>0</x>
<y>-2.9</y>
<z>7.9</z>
<pitch-deg>10</pitch-deg>
</view>
<frustum>
<top>0.0609</top>
<bottom>-0.0609</bottom>
<left>-0.2000</left>
<right>0.2000</right>
<near>0.4</near>
<far>120000.0</far>
</frustum>
</camera>

<!-- HDTV pane 3 - Rear view -->
<camera>
<window>
<name type="string">HDTV</name>
</window>
<viewport>
<x>0</x>
<y>0</y>
<width>320</width>
<height>240</height>
</viewport>
<view>
<heading-deg type = "double">0</heading-deg>
<x> 0.00</x>
<y> -2.20</y>
<z> 13.40</z>
<pitch-deg>10</pitch-deg>
</view>
<frustum>
<top>0.235</top>
<bottom>-0.235</bottom>
<left>-0.2000</left>
<right>0.2000</right>
<near>0.4</near>
<far>120000.0</far>
</frustum>
</camera>



<gui>
<window>
<name type="string">HDTV</name>
</window>
</gui>
</camera-group>
</rendering>
</sim>
</PropertyList>

--------------------------------------------------------------