virtualbox.org

I have installed Virtual Box 4.2.4 on a Windows 8 Pro machine running a 3.2 GHz Ivy Bridge CPU with 32 GB of memory. I am running a Solaris 11.11 virtual machine with Oracle 11.2.0.3 running on it.
When waking up the machine from standby Virtual Box just hangs. There is only a black screen and I cannot get to the screensaver to enter my password. There is no much CPU activity present.
Is there any known issue?

Thanks