Motorola E398 supports MIDP 2.0, but not Manager.playTone?

Question

I am a newbie J2ME Developer who wants to write a J2ME game because of a very simple motive: to write something that runs on my Motorola E398 Mobile phone, and to impress my friends. Nice motive, Err :-P
Anyway, I was wondering:
- Is there any discussion group or forum which Motorola mobile phone developer mostly hang out at? I don't know if it's appropriate for me to ask machine specific question here.
- I wrote a simple music keyboard application using Java Wireless Tookit 2.1. The application ran fine on emulator, but failed to run on my E398 phone. I suspect that it was the following lines that cause trouble:
     try {
     Manager.playTone(ToneControl.C4, 100, 80);
     } catch (Exception ex){}
E398 supports MIDP 2.0, and MIDP 2.0 provides javax.microedition.media.* for tune playing. Then how come the above code failed?
Deecay

Answer 1

Sorry, here's more info:
(1) When I tried to run my application (MobilePiano) on the mobile, it started, and within 1 second, popup a message saying "Application Error" and then back to the Java app selection menu.
(2) The application WORKS under the "Run MIDP Application ...) that comes with J2ME Wireless Toolkit.
(3) the application FAILED under the "Motorola Launchpad for J2ME", which is part of the Motorola SDK v4.4.2 for J2ME (http://www.motocoder.com/motorola/pcsHome.jsp?rNum=-1001393858&node_name=SDK)
The founding (3) is important, because now I know that there's one emulator that behaves sort of consistant with my Motorola E398. I also looked into the documentation in the Motorola SDK and found one sound test sample code, and was puzzled when I found out that the sample app use the following lines to play sound:
     AlertType.ALARM.playSound(myDisplay);
     AlertType.CONFIRMATION.playSound(myDisplay);
     AlertType.ERROR.playSound(myDisplay);
     AlertType.INFO.playSound(myDisplay);
That doesn't work for the piano app I want to write.
Deecay