Wirelessly posted (Samsung Galaxy S: Mozilla/5.0 (Linux; U; Android 4.0.4; en-us; SGH-T989 Build/IMM76D) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30)

From what I have been able to find out, the 5 pin MHL port can not do both high definition tv and usb simultaneously, the 11 pin MHL connector can. Am I correct?
The reason I am asking is that my son has an Atrix, which has a separate micro HDMI and USB ports, and he connects to his lapdock. If the 5 pin MHL port can support both USB and HDTV protocols, I could use it too. Of coursr, I will need an adapter that plugs into the MHL port on my Galaxy S II port and splits into USB and HDMI. I haven't seen anything like that.