Passing a zero UID to SendMessage on the 6600 seems to have no effect; I tried setting the UID to TUidApaMessageSwitchOpenFileValue and that seems to do something on the emulator.
task.SendMessage( TUid::Uid( TUidApaMessageSwitchOpenFileValue ), *param8 );
Could someone at Nokia confirm this is the correct procedure to use for the 6600 please?
Edit: after trying on the device, this seems to have no effect! Can someone post a working example for the 6600 please?