VirtualBox v4.0.12 is released. VirtualBox is a general-purpose full virtualizer for x86/x64 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.

VirtualBox v4.0.12 Changelog:
This is a maintenance release. The following items were fixed and/or added:

Mac OS X hosts: Lion fixes
Solaris hosts: fixed preemption issue with Solaris 11 hosts (builds 166 and above)
VBoxManage: more convenient configuration of storage controller attachments by automatically determining the port or device parameter when a storage controller has only one port or device per port (bug #9188)
Storage: fixed possible data corruption under certain circumstances whith VHD and Parallels images (bug #9150)
Storage: fixed access to CD/DVD images beyond 4GB when using the SATA controller (bug #8592)
Floppy: make it possible to unmount a host floppy disk (bug #6651)
Networking: fixed the problem with segmentation offloading when several VMs were transmitting at once
3D support: fixed GL_VERSION string for different locales (bug #8916)
Sources: fixed USB 2.0 support using extension packs for non-official builds
Solaris Additions: fixed automounting of shared folders (bug #8014)

Download: VirtualBox v4.0.12
Source: Here