Oracle announced a 3.2.8 maintenance release of VirtualBox.  And it fixes quite a few things, including:

• VMM: properly terminate the VM with an error if the guest is trying to switch to the PAE mode but PAE is disabled in the VM settings
• GUI: switch to native file dialogs (Windows hosts only)
• GUI: don't use native file dialogs on KDE hosts (Linux hosts only)
• 3D support: fixed GL_EXT_texture_sRGB support
• PXE: fixed ZENworks PXE boot regression
• OVF: fixed slower export and larger images under certain circumstances (3.2.6 regression)
• USB: properly signal an interrupt if the port suspend status changes
• USB: respect the remote-only filter
• USB: avoid VM hang when changing the configuration of certain devices (Windows hosts only)
• USB: fix a crash with older Linux kernels and non-ASCII characters in device strings (Linux hosts only)
• PageFusion: fixed conflict with the guest execution feature
• PageFusion: fixed stability issues with a large number of VMs
• PageFusion: fixed host crashes with guest SMP and Win64 guests
• Memory ballooning: fixed problems restoring VMs with pre-allocation enabled
• Bridged networking: fixed performance issue with GRO enabled on bridged device
• Hostonly networking: fixed performance issue (3.2.6 regression)
• Hard disks: fix auto-reset of immutable disk at VM startup
• BusLogic: several fixes for Windows NT/2000 and SCO OpenServer guests
• LsiLogic: fixed I/O errors under rare circumstances
• Sharing disks: support for attaching one disk to several VMs without external tools and tricks (see here for a short explanation)
• Shared folders: several fixes and performance enhancements for Solaris guests
• Solaris Installer: added support for remote installations
• Guest Properties API: correctly support enumerating the properties of a running VM with an empty "patterns" field
• Guest properties: properly delete transient properties on shutdown
• RDP video redirection performance improvements and stability fixes
• Settings: silently fix host audio driver when reading machine XML settings files or OVF written by VirtualBox on a different host OS, for example convert DirectSound to PulseAudio
• Settings: properly store the NAT network setting in XML settings file version 1.10 and later
• VBoxManage: handle differencing images with parent UUID correctly in subcommand openmedium disk
• Web service: enabled HTTP keepalive for much better performance
• Web service: added timestamps to logging output
• Web service: treat 8-bit strings as UTF-8 not ASCII
• X11 Additions: fix for Xorg 6.8 guests (e.g. RHEL4)

You can download VirtualBox 3.2.8, here.