Yes, it is possible ...
Maybe it can be done with the MIDlet.platformRequest() method. This may allow you to start a native app to handle a certain URL. Theoretically,
you should be able at least to start a voice conversation or a MIDlet installation. This may start native applications on the device, but it is platform dependent what apps can be started ...
Dunno if it�s useful, but if you want to start a MIDlet (in the same MIDlet suite), then it should be easier ... consider using the Push Registry API: PushRegistry.registerAlarm().