I have OpenSolaris 2009.06 installed as a guest operating system on Virtualbox 3.0.4 under OS X 10.5.8. The VirtualBox guest additions have been installed. All available updates have been applied to both operating systems and VirtualBox.
The audio does not work. No sound heard on boot, the volume control in not active, and I get a "Could not open resource for wrtitng" error when I try to play a sample sound from the sound preferences diaglog.
The VirtualBox audio settings are
Host Driver: CoreAudio Controller: ICH AC97