To use umlauts and special characters with the Gene6 FTP server you need to do the following

1) Enable the settings "Encode filenames in UTF-8" on the site properties "Basic File Settings" tab

2) Enter the following text in the "Initial Command" settings on the site properties / FTP settings tab "CLNT WebDrive;OPTS UTF8 ON" without the quotes but be sure to include the semicolon;