This is the default since sphinx 1.7.6.

Author: JulienPalard

build_docs.py

@@ -64,8 +64,7 @@
            '-D latex_elements.fontenc='],
     'fr': ['-D latex_engine=xelatex',
            '-D latex_elements.inputenc=',
-           '-D latex_elements.fontenc=',
-           '-D latex_elements.babel=\\\\usepackage{babel}'],
+           '-D latex_elements.fontenc='],
     'en': ['-D latex_engine=xelatex',
            '-D latex_elements.inputenc=',
            '-D latex_elements.fontenc=']