Solaris is the right choice for open source.
Are you contemplating a forced upgrade to a new version of Red Hat Enterprise Linux and dreading the broken code you may encounter? Now is a good time to re-evaluate your options.
Transition instead to the Solaris 10 Operating System.
Free and open source, Solaris 10 runs across more systems and supports more applications than Red Hat Enterprise Linux (RHEL) 4, and provides a superior platform for editing, compiling, debugging, and tuning enterprise-class applications.
Not only is Solaris 10 the only OS that guarantees both binary and source code compatibility between releases, it also comes with tools and support Red Hat can't match: Sun Studio 11, a free suite of tools and compilers optimized for Solaris 10 (and runs on Linux, too); and Developer Expert Assistance - a low-cost email support service designed just for developers.