Confusion in command line interpreter

Question

I installed manual doc for linux programmer on Ubuntu using Synaptic for French documentation. But when I run man printf to see the documentation of printf() in C library stdio.h, I dont get this. I get this:

PRINTF(1)                          Commandes                         PRINTF(1)
NOM
       Printf - Formater et afficher des données
SYNOPSIS
       printf FORMAT [PARAMÈTRE] ...
       printf OPTION

But I obtain the correct output for scanf as I want in french. An ideas?