Volunteer in Australian hospital!

Hi! :-) This is Jonas Schmalzl from Würzburg, Germany. Last year I graduated from highschool and in October 2008 I began studying Medicine at the University of Würzburg. However, within the first four terms I have to volunteer for 90 days in an hospital. I have the choice to either do this in an hospital in Germany but it's possible to go abroad as well. After I got the opportunity to participate in an exchange year in New Zealand in 2006 I dreamed of going to Australia ever since. Who of you can help me to make my dream come true? I tried emailing many hospitals but I didn't get one proper answer. Thanks for your help in advance. Jonas P.S. Emails to jonas.schmalzl@web.d please! :-)