Gender-exclusive names all mixed up.

I've always found odd how gender-exclusive names are so mixed up in English. :confused:

In Spanish, María is female and Pedro is male; all names make clear the gender of the owner. But in English things doesn't seem to be that simple:

Rene Descartes = male philosopher.
Rene Russo = female actress.

Vivian Hsu = female singer.
Vivian Campbell = male guitar player for Def Leppard

Kelly Johnson = male engineer who created the U-2 airplane.
Kelly Johnson = female singer for UK rock band Girls' School.

Do you know any other examples?