The premiumize.me upload server has started truncating the multipart
file name at the first ";", so uploading "a;b.txt" created a file
called "a" and the upload then failed with "object not found".
Directory creation and renames still accept ";", so files whose names
contain ";" are now uploaded under a temporary name and renamed into
place. The encoding is left unchanged so existing files and
directories containing ";" remain accessible.