VMM: more work on improving the emulation of certain MSR registers (e.g. bugs #12224, #12544)
VMM: fixed a VERR_INVALID_RPL Guru Meditation when booting certain guests (bug #11350)
VMM: experimental support for SSE 4.1 / SSE 4.2 passthrough, see the manual for more information how to enable it (bug #8651)
VMM: fix for recent Linux kernels with software virtualization
GUI: experimental HID LEDs synchronization for Windows hosts, see the manual for more information
GUI: warn the user if the Oracle Extension Pack is not installed and the user tries to activate the remote display feature (bug #9104)
GUI: make sure that a minimized guest (using mini toolbar in fullscreen/seamless mode) keeps the minimized state (bug #12199)
GUI: popup banner's "do not show this message again" check-box replaced with corresponding button
GUI: network adapter cables can now be connected/disconnected directly through the running virtual machine Devices / Network menu a Network status-bar indicator
GUI: the new VM wizard now proposes 64-bit guests on 64-bit hosts by default; better distinction between 32-bit OS types 64-bit OS types (bug #12533)
GUI: better error message if appliance import fails (bug #12657)
GUI: allow to set host-combination to ‘None' using the Global settings / Input page (bug #12730)
GUI: don't switch the guest to a black screen during online snapshot merge (4.3 regression)
VBoxManage: when exporting an appliance, support the suppression of MAC addresses, which means they will be always recreated on import, avoiding duplicate MAC addresses for VMs which are imported several times
AHCI: fixed a VM hang during suspend under certain circumstances
AHCI: fixed a VM hang during online snapshot merge under certain circumstances
AHCI: fixed a bug which resulted in Windows XP guest hangs if a SATA CDROM is attached (bug #12417)
AHCI: fixed a Guru Meditation under certain conditions
AHCI: ejecting a CD/DVD medium failed under certain conditions
AHCI: disk hotplugging fixes
NAT: transparent handling of host sleep/resume and network configuration changes if the dnsproxy is enabled or if the hostresolver is used (bug #12441)
NAT: fixed crash and misbehaviour under some circumstances with ICMP packets having TTL=1
NAT Network: fixed IPv6 reassembly
NAT Network: ping proxy implemented
OVF: fixed reading of the OVF 0.9 section element (4.3 regression; bug #12345)
OVF: several fixes
3D: several fixes, multiscreen fixes (e.g. bug #9124)
3D: include 3D content in captured videos (bug #12666)
3D: include 3D content in captured screenshot (bug #11758)
VGA: proper handling of legacy graphics modes if the Guest Additions are active (bug #6649)
USB: fixed crash during isochronous transfer under rare circumstances
BIOS: better disk geometry handling of SCSI drives
API: fix crashes in Java API clients using the XPCOM binding, happened with output parameters only (bug #11232)
VBoxSVC: documented the handling of host power management events (see the manual for more information) and added an extradata item for configuring the handling of the battery-low event (bug #9925)
VBoxSVC: fixed a bug which could trigger a crash if a VM snapshot was restored the second time and the VM has associated bandwidth groups (bug #12569)
VBoxSVC: properly detect ifconfig if located in /bin (bug #12713)
Shared Folders: fixed a failure to restore transient shared folders when starting a VM from a saved state (bug #12578)
Mac OS X hosts: fixed issue when the application icon was frozen in the dock if the bridging interface was not connected to a network (bug #12241)
Linux hosts: also consider the physical package ID when determining the number of physical CPU cores
Linux hosts / guests: don't warn in kernel log if memory allocation fails (bug #11171)
Solaris hosts: fixed the autostart SMF script (bug #11720)
Windows hosts: fixes for non-ANSI code page user names and similar environment contents (bug #12596)
Windows hosts / guests: fixed setting and using a guest user's process environment variables (relevant for Guest Control)
Windows Additions: fixed handle leaks in VBoxTray (bug #12563)
Windows Additions: fixed a crash while detecting active guest users
Windows Additions: fixed restoring backed up D3D files on XPDM -> WDDM upgrade
Guest Control: fixed setting and using a guest user's process environment variables
Linux Additions: support Enterprise Linux 6.5 kernels (bug #12505)
Linux Additions: fixed CPU hot-remove on newer Linux kernels
Linux / Solaris Additions: don't automount a shared folder which is already mounted
X11 Additions: support X.Org Server 1.15 (bug #12623)
VirtualBox 原先是德国一家软件公司InnoTek所开发的虚拟系统软件（已被SUN收购，而SUN已被Oracle收购），它不仅具有丰富的特色，而且性能 也很优异。VirtualBox 可以在 Linux 和 Windows 主机中运行，并支持在其中安装 Windows (NT 4.0、2000、XP、Server 2003、Vista)、DOS/Windows 3.x、Linux (2.4 和 2.6)、OpenBSD 等系列的客户操作系统。假如你曾经有用过虚拟机软件的经历的话，相信使用 VirtualBox 不在话下。即便你是一个新手，也没有关系。VirtualBox 提供了详细的文档，可以助你在短期内入门。
