As promised, the first version is ready to download from this link
http://dremadur.de/N900FTP.zip

Please use this version on your own risk, it is nothing more than a pre release.
Nevertheless I'm waiting for every feedback to get this software running smoothly.

After download, unzip and put somewhere in your filesystem. From commandline execute then
# python N900FTP.py

I'm not quite sure, but I think the package "PyQt4 Full install" is needed.

Open issues are:
- After downloading / uploading the local or remote view is not updated
--> workaround, select another dir and jump back
- Recursive deleting remote directories is not working
- Bookmarks are not implemented yet,
--> every time the login information has to be re-entered
- No progressbar of what is happening
--> only commandline sth. is logged
in combination with the first issue it's not so easy to realize when a transfer is finished

HowTo use the application:
1. After start click on menu -> Open Location
2. After successfull connect the left list shows the local filesystem, the right list shows the remote server
3. Any action is started, by clicking and holding on a list entry. The context menu, which opens, offers all possible functions
4. To switch from Home-Folder to Memory-Card, open the menu --> Switch Local Dir and enter /media/mmc1



@aspidites: Thanks for providing the link. It seems most of the instructions are based on using scratchbox environment. I hope I'll find another way, because I haven't set it up.