Oracle is <A HREF="http://www.cio.com/blog_view.html?CID=23895">doubling the number of Linux systems</A> pretested by its Validated Configurations program. The database and applications vendor has also added three partners to the Linux systems recommendation program, it will announce Tuesday at the LinuxWorld conference in San Francisco. Oracle unveiled Validated Configurations in June to let users know which Linux systems configurations it had pretested. The idea was to provide an additional comfort level for Oracle customers looking to run particular combinations or stacks of software, hardware, storage and networking technologies on the open-source operating system.