Java – J2ME Midlet exception :IOException reading reader invalid first byte

I didn't understand whether you mean putting midlet in paused state or just stopping execution for specified time.

If it's the latter, actually I don't undesrtand, why you don't want to use Threads, this is no big deal. You just insert three following lines wherever you need:

try {
    Thread.sleep(10000);
} catch (Exception ex) {}

That's all, nothing too complicating.

This is definitely a JVM bug. startApp() should be called only once at startup and can't be called again until pauseApp() is called or you call notifyPaused() yourself.

What I suggest is the following code:

private boolean midletStarted = false;

public void startApp() {
    if (!midletStarted) {
        midletStarted = true;
        //Your code
    }
}

This way you can track midlet state changes. But in fact it is better that you don't use this method at all and use constructor instead.

Oh, by the way, I don't think that there are some multiple instances or something like that, this is merely a JVM error.