special character filename on Host - howto delete ?

Hello, I have a problem with special characters in a filename like "Präsident.txt" on my Webserver Provider...

With SmartFTP I could upload all files, but now, when I want to delete them,
I got the Errormessage "[19:27:44] 550 Präsident.txt: No such file or directory "

First of all, how to delete and how I can set up a filter in SmartFTP, that this not occurs another time - I mean uploading bad characters in a filename by chance...

Thank you very much
Dieter

Hello ..

Please post the complete log from the Remote Browser.

Regards,
Mat

the error message is - when i click on the del button:

[14:06:50] 213 20090221145339
[14:06:50] Timezone offset: 0 seconds (0.0 hours)
[14:06:59] DELE Obama als neuer Präsident.flv
[14:06:59] 550 Obama als neuer Präsident.flv: No such file or directory

best regards
Dieter

Please post the complete log from the Remote Browser.