If you want to know which versions of Softimage, Maya, or Max will work with Softimage 2012, you can find that info on autodesk.com/softimage-crosswalk, the Crosswalk download page. In brief, these are the supported versions:
- Softimage 7.5 and later
- Maya 8.5 and later
- 3d Max 2009 and later
eX-SI 