From the release notes of Mac OS 10.5.6, amongst a number of bug fixes and performance improvements:
Addresses inaccuracies with Calculator when the Mac OS X language is set to German or Swiss German.
I'm not sure what boggles me most: that there's something unique about German (and Swiss German) that it interferes with a calculator, or that it's taken until now to find the bug.
It's probably an obscure bug involving unit conversions or something weird like that, but still: numbers fail in German?
(Insert your own Weimar Republic joke here.)
