When uploading files with non-ASCII characters I get UnicodeEncodeError:
Exception Type: UnicodeEncodeError at /admin/studio/newsitem/add/ Exception Value: \
Hope this would help. In my case, I'm running django through daemontools.
Setting
export LANG='en_US.UTF-8' export LC_ALL='en_US.UTF-8'
in run script before executing manage.py resolved the issue with uploads filename