Git and PowerShell and German umlauts
There's an unofficial installer for the experimental Unicode version of msysgit which you might want to give a try. Feedback to that installer is appreciated on the msysgit mailing list.
I have the same problem (I'm from Sweden). Seems that if you use Git Extensions and commit through that the umlaut characters are fine. I use:
[i18n] commitencoding = windows-1252 logoutputencoding = Windows-1252 filesEncoding = Windows-1252
Would love a solution to the powershell/command line problem though.
There known quirks and issues with MSysGit and unicode as well as simple casing. Instead of struggling with this, if I were in your shoes, I would use VritualBox with a small Linux server image (no need for desktop), and use a shared directory between host and guest OSes. This way you can use Git in Linux but develop on Windows. Open a terminal to remote to the server and you can alt+TAB to the window just like you would with MSysGit.