After a fresh installation of Debian Lenny, I wanted to use a quite very recent version of VirtualBox.
One solution is the Debian backports : Here are the VirtualBox packages available
To make VirtualBox work well, you need to install the following packages : virtualbox-ose, virtualbox-ose-qt and virtualbox-ose-source
Here are the version(s) available for each package mentioned above :
virtualbox-ose : 3.0.12-dfsg-1~bpo50+1 (for i386)
virtualbox-ose-qt : 3.0.12-dfsg-1~bpo50+1 (for i386)
virtualbox-ose-source : 3.1.4-dfsg-1~bpo50+1 (for all platforms)
As you may have noticed, virtualbox-ose-source version is higher than the ones above. As a test, I installed all of them. I compiled the modules needed with module-assistant. I failed to launch a virtual machine.
Here is the message I got :
VBoxHeadless: Error -1912 in supR3HardenedMainInitRuntime!
VBoxHeadless: RTR3Init failed with rc=-1912
Running as a normal user the command vboxheadless, I encountered the same message :
fool@localhost:~$ vboxheadless
VBoxHeadless: Error -1912 in supR3HardenedMainInitRuntime!
VBoxHeadless: RTR3Init failed with rc=-1912
VBoxHeadless: Tip! It may help to reinstall VirtualBox.
The only workaround I found for this problem is to install the Sun’s package available here .
To install it :
root@localhost:~# dpkg -i virtualbox-3.1_3.1.4-57640_Debian_lenny_i386.deb
Make sure that the good modules are loaded correctly :
root@localhost:~# lsmod |grep vbox
vboxnetadp 6436 0
vboxnetflt 12332 0
vboxdrv 155144 2 vboxnetadp,vboxnetflt
As a last test, run the following command :
root@localhost:~# /usr/bin/VBoxHeadless
You should have the message below :
Sun VirtualBox Headless Interface 3.1.4
(C) 2008-2010 Sun Microsystems, Inc.
All rights reserved.
Usage:
-s, -startvm, –startvm <name|uuid> Start given VM (required argument)
-v, -vrdp, –vrdp on|off|config Enable (default) or disable the VRDP
server or don’t change the setting
-p, -vrdpport, –vrdpport <ports> Comma-separated list of ports the VRDP
server can bind to. Use a dash between
two port numbers to specify a range
-a, -vrdpaddress, –vrdpaddress <ip> Interface IP the VRDP will bind to
-c, -capture, –capture Record the VM screen output to a file
-w, –width Frame width when recording
-h, –height Frame height when recording
-r, –bitrate Recording bit rate when recording
-f, –filename File name when recording. The codec
used will be chosen based on the
file extension

This is the VirtualBox? OSE 3.1.4 that can be used on all Debian and its derived distros. Tested on India Force Linux, which itself is a live cd based on stable Debian Lenny.
Here is the link – http://code.google.com/p/virtualboxoseforifl/
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