There may be another way.
More recent versions of Blender can export files in Milkshape3D format. Now Milkshape is only available for PC, but there is a Mac version of a Milkshape-ish clone (better in my opinion) that opens Milkshape files.
It's called Jalada Sculpture.
It can then export CAL3d in the proper formats.
That way you can use the latest version of Blender (2.76).
You can download the skeletons in Milkshape format here, that either Blender or Jalada can read.