The correct name of the soup is "Soto Betawi".
I just called JAVA restaurant and confirmed the dish.
For those who just heard this: it is very unique and flavorful soup consist of lamb meat chunks, white broth and other goodies. It is unlike anything that you normally found here in U.S. but very delicious. I highly recommend it. JAVA is located in Geary right after the tunnel if you come from Japantown.
Also Andrew, see the post below for new dishes to try.
I think you are a lucky guy to have liked Indonesian food - it is another planet and zillions of new things to explore. I think it is a treasure for gourmet lovers because they have so many unique and distinct foods. Let me know how your gourmet adventure went !!