Certainly not. It's just one single sentence. It would be a different matter if there the source was'nt indicated, but as you see this isn't the case.

Hinweis: Das Urheberrecht für diese Textstelle liegt beim ANNE FRANK-Fonds in Basel.
Ich werde dort um eine Erlaubnis um das Anführen weiterer Sätze aus dem Tagebuch von Anne Frank ersuchen.

@arcticmonkey
>The corpus is released under a Creative Commons license.<
The problem you mentioned is really very important and has to be considered very seriously. Until now I wasn't quite aware of the possible legal implications caused by this fact.

Copyright according to French law (and as me and Trang are French, and that the server is hosted in France, and now tatoeba is a french non-profit association, so in case of legal problem, there's huge chance that the French leglislation apply), every work, as soon as it is "enough" to need some creative spirit to be done, fall under copyright, even a single sentence if is structure, construction, is enough complex to make it "identifiable". So I think here there's huge chance that it falls under this case.
By the way in France, works fall under the public domain after 70 years of the author death or translator death(if you're putting here a translated text)

And actually in France, even public domain work stil require an "attribution" (i.e you can quote a complete work of Victor Hugo or Goethe for example, but you need to say it's from Goethe, this "right" is forever), so quote need to be tagged, or if you can't, to be added in comments.