Yesterday I removed R2.11 from my system (Win7, 64bit), since I´m working on R2.13.
Since then i get an error message:
> require(rJava) Lade nötig
I finally solved the problem:
It seems that rJava searches for jvm.dll in ~\Java\jre6\bin\client. However this folder didn´t exist on my system (jvm.dll was in ~\bin\server).
So I just made a copy of jvm.dll in a folder ~\bin\client\ and added this to the path.
Now everything works fine!