Today, I successfully installed Solaris 9 (x86) guest operating system on Ubuntu 9.10 (Karmic Koala) host operating system. I used VMware Player to virtualise the Solaris 9 OS.
I had bought the Solaris 9 media back around 2003, and have been waiting for the right time to install the software on a spare computer (so I have been thinking, for years). But thanks to VMware Player, installing Solaris 9 and other interesting operating systems is now much easier than ever.
To do this install, I followed the directions from VMware on Solaris 9 guest OS: http://pubs.vmware.com/guestnotes/wwhelp/wwhimpl/common/html/wwhelp.htm?context=guestnotes&file=guestos_solaris9.html
Here are the results (I know, the display settings need some work)...