Are there plans to support UML 2 or XMI 2 in IBM Rational System Architect (SA) and what are the reasons for persisting with the current versions?
The supported versions (UML 1.4, XMI 1.1) limit the sharing of data between applications impacting the usefulness of SA.
SA supports a subset of UML 2. If you want full UML 2 support you are recommended to use IBM Rational Software Architect (RSA). You can then use the RSA-SA integration to exchange data between the tools. The SA integration with RSA is the strategic way forward to enabling exchange of UML information via XMI 2.0 from or to SA.