如何将所有文件夹和文件重命名为Linux下的小写字母?

I have to rename a complete folder tree recursively so that no uppercase letter appears anywhere (it's C++ sourcecode, but that shouldn't matter). Bonus points for ignoring CVS and SVN control files/folders. Preferred way would be a shell script, since shell should be available at any Linux box.I have to rename a complete folder tree recursi