14 DAY TRIAL // A new release of VirtualBox is available for Mac OS X from Oracle developers who’ve highlighted a trio of Mac-specific changes, as well as numerous general enhancements and fixes affecting all supported platforms.
Labeled as a maintenance release, VirtualBox 4.0.8 fixes incompatibility with recent Mac OS X versions in 64-bit mode, according to Oracle.
The buyers of Sun Microsystems fail to mention exactly which versions of the Mac OS were targeted here, therefore we are left to guess that the program was also tested against betas of Apple’s OS X 10.7 ‘Lion.’
VirtualBox development cycles have always included experimental support for unreleased OS versions; therefore, it makes sense to assume the virtualization app will be compatible with Apple’s Lion out-of-the-box.
Also for Mac OS X hosts, Oracle has fixed incompatibility with hosts with more than 16 cores, as well as painting corruptions on a second monitor in 64-bit mode.
The changelog mentions one GUI enhancement that restores functionality to set an empty host key to disallow any host key combination.
This was a version 4.0.6 regression bug, as was an issue with Shared Folders - “don't stop mounting the other valid folders if one host folder is inaccessible,” reads the bug’s description.
Other noteworthy changes in VirtualBox 4.0.8 include:
VBoxManage: added controlvm screenshotpng subcommand for saving the screenshot of a running VM in PNG format
VBoxHeadless: fixed potential crash during shutdown (Windows hosts only)
NAT: built-in services use the correct Ethernet addresses in Ethernet header and in ARP requests
SATA: fixed guest disk corruption under rare circumstances (only relevant for guests with more than 2GB RAM)
3D support: fixed a potential crash when resizing the guest window.
VirtualBox requires an Intel-based Mac, plenty of RAM (above 2GB for good performance), around 100MB of storage for the program itself, and whole gigs of leftover disk space for the subsequent operating systems you plan to install in its virtual machines.