OK... I am seeing spurious abrupt terminations of my app (no exception, no message at all), which occur only on S60 5th edition devices. I have finally tracked it down to the MIDP high-level UI implementation.
It appears to relate to the construction and tear-down of Forms and their contained Items.
I've attached a sample app that reproduces the problem.
I can reproduce this issue on:
* 5800XpressMusic, 20.0.012.C02.01
* N97 mini, 12.0.110.C01.01
It would be of great help to know what (internally) is causing this problem, and if there is any work-around more specific than "don't create and destroy Forms or Items".