I have been trying to get this working for a few weeks now. I am trying to install QGIS Dufor (2.0.1) and Saga GIS from the Unstable branch of the UbuntuGIS PPA. When I attempt to do this I get the following error
The following packages have unmet dependencies:
saga : Depends: libsaga (= 2.0.8+dfsg-4~raring) but 2.1.0-0~raring2 is to be installed
E: Unable to correct problems, you have held broken packages.
It appears that the dependencies have not been updated. When I try to install saga from the Johanvdw/saga-gis ppa i am told that two dependencies are too old and required by QGIS. The only way I can get both programs installed at the same time is to install the QGIS nightly build. When I do things this way Sextante can not seem to locate the saga routines. With the changes in sextante now that it has been added to trunk, there is no longer a field to specify the directory that SAGA resides in. I have a similar topic open HERE. I am out of ideas at this point.