Up to Android 2.2 I know I can use reflection and terminate the call through getITelephony.
However, as of 2.3 this no longer works because even if you grant the MO
The call() , endcall() functions work fine for me as well. But there is also another way tha works without using iTelephony.aidl. Its published in this post. BTW I think google already knows but for some reason they havent done anything with the rest of functions, wich is good!!!
http://androidbridge.blogspot.com/2011/05/how-to-answer-incoming-call-in-android.html