the symbol is MHI but you'll need to open a HK account and have to fund in HK dollars. However, the universal account which should be released shortly will enable you do do it from one account (you'll just have to fill the online application for the univeral account and fax the risk disclosure agreement (HK requires a physical copy of the signature page). As mentioned in another post, the universal accounts are currently being beta tested by a number of clients and will be opened for all shortly.
charting: there are a couple that might have free charts but nothing great. For a small fee you can try prosticks. On the IB web discussion board under Asia there are a few links. However, when qcharts and quote tracker finish integrating with IB, you should be able to use them. -- one last thing. If you are looking at charts, you should use HSI since that is the main market. MHI will simply follow HSI within 1-2 ticks.