From The Register late last week
The OpenSolaris project and Sine Nomine Associates have announced that Sirius – a Solaris port for IBM mainframes – is ready for action.
The Sirius variant of Solaris runs atop IBM’s z/VM operating system, which is also one of the pioneer virtualization environments for servers. The Sirius code is a 64-bit implementation of Solaris that runs on z9 or z10 mainframe processors and requires z/VM 5.3 or later.
…You can get the Sirius binary code through Sine Nomine’s Web site and the open source code through the OpenSolaris site, which is where development for OpenSolaris for x64 and Sparc processors as well as the related “Polaris” project for Power-based machines is hosted. A prototype of OpenSolaris running on mainframes was announced a year ago, by the way.
More in the article.