[gm45] xrandr recognizing TV1 as connected although isn't

Binary package hint: x11-xserver-utils

On startup and login sometimes there is an additional monitor recognized.
At least after login I can see it when the desktop icons at the bottom right are shown with increased width and I can move the mouse far outside the screen.

Sometimes on startup I don't see the user selection box and only after pressing CTRL+ALT+F1 and CTRL+ALT+F7 I get it back. - Maybe there it sometimes tries to display the login form on the second monitor...

Here is my output of my Dell Latitude E-5500 laptop:
xrandr --current
Screen 0: minimum 320 x 200, current 2288 x 900, maximum 8192 x 8192
VGA1 disconnected (normal left inverted right x axis y axis)
LVDS1 connected 1440x900+0+0 (normal left inverted right x axis y axis) 331mm x 207mm
   1440x900 59.9*+ 59.9
   1360x768 59.8
   1152x864 100.0 85.1 85.0 75.0 75.0 70.0 60.0
   1024x768 85.0 75.0 70.1 60.0
   832x624 74.6
   800x600 85.1 72.2 75.0 60.3 56.2
   640x480 85.0 72.8 75.0 59.9
   720x400 85.0
   640x400 85.1
   640x350 85.1
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP3 disconnected (normal left inverted right x axis y axis)
TV1 connected 848x480+1440+0 (normal left inverted right x axis y axis) 0mm x 0mm
   848x480 30.0*+
   640x480 30.0 +
   1024x768 30.0
   800x600 30.0

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: x11-xserver-utils 7.5+1ubuntu2
ProcVersionSignature: Ubuntu 2.6.32-24.39-generic 2.6.32.15+drm33.5
Uname: Linux 2.6.32-24-generic i686
Architecture: i386
Date: Fri Aug 13 16:36:09 2010
DkmsStatus:
 vboxnetadp, 3.2.8, 2.6.32-24-generic, i686: installed
 vboxnetflt, 3.2.8, 2.6.32-24-generic, i686: installed
 virtualbox-ose, 3.1.6, 2.6.32-24-generic, i686: installed (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!)
 vboxdrv, 3.2.8, 2.6.32-24-generic, i686: installed
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
MachineType: Dell Inc. Latitude E5500
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-24-generic root=UUID=0c5230d6-05d2-47c8-9325-347fe42d71f9 ro quiet splash
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: x11-xserver-utils
dmi.bios.date: 04/15/2009
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A11
dmi.board.name: 0DW634
dmi.board.vendor: Dell Inc.
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA11:bd04/15/2009:svnDellInc.:pnLatitudeE5500:pvr:rvnDellInc.:rn0DW634:rvr:cvnDellInc.:ct8:cvr:
dmi.product.name: Latitude E5500
dmi.sys.vendor: Dell Inc.
glxinfo: Error: [Errno 2] No such file or directory
system:
 distro: Ubuntu
 codename: lucid
 architecture: i686
 kernel: 2.6.32-24-generic

[lspci]
00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07)
     Subsystem: Dell Device [1028:0263]