tfPIN=new TextField("PIN:", null, 4, TextField.Numeric|TextField.PASSWORD);
... other code to launch the form.
The idea is, that the user can enter a 4 digit PIN code to unlock some data. Now, on a Nokia 6230 when pressing Edit the user is prompted for the PIN code. The PIN code is masked out with asterisks (as expected). On the Settings form the PIN code is shown even though the TextField.PASSWORD constraints has been given.
Why is that?
maybe you have to accept that every phone have different implementation and spec of Java. even they are in the same series....
so, you may need to solve this by trial and error.
and I can say that this cost most of the development time.