Just received this from the Bundesregierung mailing list:

"Les étrangers qui vivent déjà en Allemagne sont susceptibles de devoir suivre un cours d'intégration s'ils bénéficient d'aides sociales ou si un besoin d'intégration particulier est constaté, c'est-à-dire si, par exemple, les parents d'un mineur vivant en Allemagne ne parviennent pas à communiquer simplement à l'oral en allemand. Si un participant ne respecte pas l'obligation de suivre le cours, ses aides sociales risquent d'être réduites de 10 % au maximum pendant la période d'absence."

And for those who didn't had the chance to learn the language of Voltaire :-) here is the translation:
"Foreigners already living in Germany may need to follow the integration courses if they are receiving social help or if a need of integration comes to surface, i.e. for example, parents of a minor are not able to communicate verbally in a simple way in German. If one who follows these courses does not respect the obligation to follow the courses, his social help can be reduced of 10% maximum during the time he will not follow the courses."

Just to let you know that as I can see, for those already here, they will have to follow the courses only if a need is remarked.

There are other points in the newsletter but I think this one was the most relevant for us.

D.