I spent some frustrating time today unsuccessfully attempting to make the VoIP SIP Settings application work on my Nokia E70. It loaded onto the phone OK, but it would not open.
I have since discovered the E70 uses VoIP Release 1, so the application will not work on it. Only Nokia phones with VoIP Releases 2 and 2.1 are compatible with the application, according to the application's User Guide.
Here is a link to a Forum Nokia page where you can check to see if your Nokia phone is compatible with the application:
Voice over IP Service