This is an interesting issue. As far as I know, there’s only one “Googlebot”, even though different googles (ie .com, .fr) list different results. Does this mean that US Googlebot builds a database of websites (based on US geotargetting) and then ranks the websites for each different googles?
If that was the case, it would really screw you up if you had US content and other content only visible from Germany or something. I guess the safest and best way to do it is to add flags with links to the other languages. That way even if you use heavy geotargetting, those other languages would still be crawled.