Whether or not this is the correct way to handle it, I don't know, but this:

> ...lists “Eva’s Blumenladen” (Eva’s Flower Shop) and “Peter’s Taverne” (Peter’s Tavern) as usable alternatives, though “Eva’s Brille” (“Eva’s glasses”) remains incorrect

...is as German as it gets. We've made an exception to the rule that also has exceptions.

Either accept it as possible or not, this is just plain stupid.