Wallpaper on Blade (ke424c) ????

Hi! I figured out how to make and download my own ringtones (yay! ) with my new KE424C, using the phone's web browser, but I haven't found anything about wallpapers Can anyone here help me? I tried .bmp .jpg .gif .png but none worked

Must it be uploaded in binary or ascii format? I don't know, but I think pictures and other files are not uploaded the same way on a ftp server...