开源免费虚拟机 VirtualBox 4.1.22 发布，VirtualBox是一个强大的x86/AMD64/Intel64虚拟化产品，为企业和家庭免费提供使用。VirtualBox不仅具有极为丰富的功能，而且是一款高性能的产品，该软件作为开源软件是免费提供，基于GNU通用公共许可证（GPL）。
VirtualBox4.1.22 更新改变：
- VMM: fixed a potential host crash triggered by shutting down a VM when another VM was running (only affected 32-bit hosts and 64-bit OS X hosts, 4.1 regression, bug #9897)
- VMM: fixed a potential host crash under a high guest memory pressure (seen with Windows 8 guests)
- VMM: respect RAM preallocation while restoring saved state.
- VMM: fixed handling of task gates if VT-x/AMD-V is disabled
- Storage: fixed audio CD passthrough for certain media players
- USB: don’t crash if a USB device is plugged or unplugged when saving or loading the VM state (SMP guests only)
- RTC: fixed a potential corruption of CMOS bank 1
- Mac OS X hosts: installer fixes for Leopard (4.1.20 regression)
- Windows Additions: fixed memory leak in VBoxTray (bug #10808)
在ubuntu 12.04 上安装 VirtualBox 4.1.22 ：
打开终端运行下面的命令：
你需要编辑 /etc/apt/sources.list
gksudo gedit /etc/apt/sources.list
在后面加入下面的地址：
deb http://download.virtualbox.org/virtualbox/debian precise contrib
如果你是ubuntu 11.10加入下面的地址：
deb http://download.virtualbox.org/virtualbox/debian oneiric contrib
然后保存文件，运行下面的命令安装 PGP 钥匙：
wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -
更新源列表
sudo apt-get update
安装 virtualbox
sudo apt-get install virtualbox-4.1