I'm illegal

I've always known that Gretchen is an old German name. When I moved here I expected that, in a German speaking country like Switzerland, Gretchen would be familiar. Instead, I usually get laughs after I tell a native German speaker that my name is Gretchen (pronounced "Graytcheeyen" so they understand). Then I'm told that it's a very old name and no one names their children that anymore. Now I know more about my name and it's place in this country. I was told this weekend by a Swiss couple that we had dinner with Saturday night that parents are actually not allowed to name their children Gretchen. You see, Gretchen is actually a diminutive form or Margaret (which I knew), and apparently the Swiss are not allowed to name their children any name considered to be diminutive. So I suppose my name is illegal, although I suppose I get special consideration considering I'm not Swiss and I wasn't born here. We've heard stories about Swiss name regulations from American friends who've had babies while living in Basel, but this was a new one to me. I'm trying to imagine how these name rules would go over someplace like the US where you can name your baby anything you want.