Like the Windows Guest Additions, the Oracle VM VirtualBox Guest Additions for Oracle Solaris take the form of a set of device drivers and system applications which may be installed in the guest operating system.
The following Oracle Solaris distributions are officially supported:
Oracle Solaris 11, including Oracle Solaris 11 Express
Oracle Solaris 10 4/08 and later
Other distributions may work if they are based on comparable software releases.