The Object REXX programming language is an object-oriented scripting language initially produced by IBM for OS/2. It is a follow-on to and a significant extension of the "Classic Rexx" language originally created for the CMS component of VM/SP and later ported to MVS, OS/2 and PC DOS. OS/2 version of IBM Object REXX is deeply integrated with SOM. On October 12, 2004, IBM released Object REXX as open source software, giving rise to Open Object Rexx (ooREXX), now available for various operating systems: Linux, Solaris, Windows. This implementation includes a WSH Scripting Engine for Rexx. The released sources however didn't include significant piece of the SOM support. Object REXX supports multiple inheritance via the use of mixin classes.