Fresh installed Ubuntu Utopic does not boot to GUI when installed in VirtualBox

Start points:
   Ubuntu Utopic Unicorn beta2 i386 LiveCD (from http://releases.ubuntu.com/utopic/ubuntu-14.10-beta2-desktop-i386.iso).
   Fresh installed Ubuntu Utopic beta2 i386 with VirtualBox 4.3.16 (from http://download.virtualbox.org/virtualbox/4.3.16/virtualbox-4.3_4.3.16-95972~Ubuntu~raring_i386.deb)

Steps to reproduce:
  1. Try to install Ubuntu in VirtualBox.
  2. Do a first reboot of virtual installed system.

Expected results:
  Fresh installed virtual system boots normally, unity-greeter is show.

Actual results:
  Fresh installed virtual system boots to console, on <Alt+F1> show login prompt.

Temporary solution:
  Login in console mode, restart lightdm (sudo service lightdm restart) and reboot system.

Please fix this bug - make Ubuntu Utopic usable in VirtualBox installations.

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: lightdm 1.12.0-0ubuntu2
ProcVersionSignature: Ubuntu 3.16.0-17.23-generic 3.16.3
Uname: Linux 3.16.0-17-generic i686
ApportVersion: 2.14.7-0ubuntu2
Architecture: i386
CurrentDesktop: Unity
Date: Wed Oct 1 15:27:31 2014
InstallationDate: Installed on 2014-10-01 (0 days ago)
InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Alpha i386 (20140923)
SourcePackage: lightdm
UpgradeStatus: No upgrade log present (probably fresh install)