VirtualBox 4.1.20 released and ubuntu installation instructions included

VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL) version 2.

What is new in virtualbox 4.1.20

This is a maintenance release. The following items were fixed and/or added:

VMM: fixed a crash under rare circumstances for VMs running without hardware virtualization
VMM: fixed a code analysis bug for certain displacement instructions for VMs running without hardware virtualization
VMM: fixed an interpretion bug for TPR read instructions under rare conditions (AMD-V only)
Snapshots: fixed a crash when restoring an old snapshot when powering off a VM (bugs #9604, #10491)
VBoxSVC: be more tolerant against environment variables with strange encodings (bug #8780)
VGA: fixed wrong access check which might cause a crash under certain conditions
NAT: final fix for crashes under rare conditions (bug #10513)
Virtio-net: fixed the problem with receiving of GSO packets in Windows XP guests causing packet loss in host-to-VM transfers
HPET: several fixes (bugs #10170, #10306)
Clipboard: disable the clipboard by default for new VMs
BIOS: the PCI BIOS was not properly detected with the chipset type set to ICH9 (bugs #9301, #10327)
Mac OS X hosts: adaptions to Mountain Lion
Linux Installer: fixes for Gentoo Linux (bug #10642)
Linux guests: fixed mouse integration on Fedora 17 guests (bug #2306)
Linux Additions: compile fixes for RHEL/CentOS 6.3 (bug #10756)
Linux Additions: compile fixes for Linux 3.5-rc1 and Linux 3.6-rc1 (bug #10709)
Solaris host: fixed a guru meditation while allocating large pages (bug #10600)
Solaris host: fixed possible kernel panics while freeing memory
Solaris Installer: fixed missing icon for menu and desktop shortcuts

Install VirtualBox 4.1.20 in ubuntu 12.04

Open the terminal and run the following commands

You need to edit /etc/apt/sources.list

gksudo gedit /etc/apt/sources.list

Add the following line

deb http://download.virtualbox.org/virtualbox/debian precise contrib

If you are running ubuntu 11.10 add the following line

deb http://download.virtualbox.org/virtualbox/debian oneiric contrib

Save and exit the file

Now install PGP key using the following command

wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -

Update source list

sudo apt-get update

Install virtualbox

sudo apt-get install virtualbox-4.1

If you have problem with the above PPA you can download .deb package from here.Once you have deb package you can double click on it to install this package.

Source : http://www.ubuntugeek.com/virtualbox-4-1-20-released-and-ubuntu-installation-instructions-included.html