CMake-Projects with umlauts in path to project cannot compile

Short Description:
When I want to setup a cmake-project within QtCreator that contains an umlaut in the path leading to it's base folder, first CMake seems to do anything correct, but after the first try to build a project, the CMake-compiler-check fails with error U1077 from Visual Studio because the path to the generated testfile does not exist. According to verbose make-output within qtcreator the reason for this seems to be that the umlaut passed as chain of other signs.
Executing cmake from the command line does not cause this problem, so I think there's a conflict in the encoding of the messages exchanged between QtCreator and CMake (tested with 3.6.2. and the current release candidate).

Steps to reproduce:
1) Create a simple "Hello World"-project consisting of

• a main.cpp with a main function doing nothing else than printing "Hello World" to std::cout using <iostream>
• a CMakeLists.txt which builds an executable within a project e.g. named "Demo" out of the main.cpp
  2) Move that project into an folder where part of the path contains an umlaut like e.g. "ü"
  3) Open QtCreator and open the CMake-Project => CMake seems to run without error and finds the main.cpp
  4) Build the project => The CMake-compile-tests fails