In addition to many new features, last Sextante version allows to make any action from the Toolbox, not only execute algorithms but also create new models or scripts. For gvSIG users it is possible as well to execute its geoprocess like Sextante algorithms. Changes were needed in both sides so if you want to check it you will need to make checkout of trunk in both projects.
All this work will be available in the intermediate builds and release candidate of gvSIG 1.12 so that you can give your feedback. Stay tuned!
Very special thanks to Víctor Olaya for his help.