Questions regarding receiving 3G calls on my IDEOS

My Android device is 3G capable, but does not have a front-facing camera. I am on a 3G network and I don't see any "video call" option in contacts. I'm wondering if I will be able to receive video calls so that I can just see them or maybe show my primary camera (back of the phone; the only camera) to them? Also, if that was possible, can I toggle the camera off/on DURING the 3g call? And does "data packet" need to be enabled to receive 3G calls? EDIT: My device is Huawei IDEOS u8150 running Android 2.2 and if 3G video calls are not supported, can I find some custom ROM suitable for mine that can do this with the existing camera or some other workaround?