1. This reverses the action of jvmattachthread.

2. When using jvmattachthread, you must call jvmdetachthread to explicitly detach the thread from the JVM before the end of the model. If you do not call jvmdetachthread, the Java thread will persist until the JVM is unloaded. You will see a warning written to the model's error stream if you forget to do this.

3. If you called jvmattachthread multiple times from the same system thread, you must call jvmdetachthread a corresponding number of times.

4. If this is called from a thread not persistently attached to the JVM, the model will terminate with a runtime error.