I'm exploring the possibility to offer OTA wallpaper & ringtone downloading/setting services. But both Symbian OS and MIDP does not provide APIs to change the device's wallpaper & ringtone settings (as well as the power-on/off logo, etc.). I know there must be undocumented APIs for C++, why don't Nokia public these APIs? It's very useful for the operators to offer new services. As for J2ME applications, the problem is similar.