thanks and another question where are the lectures uploaded?
If lectures are uploaded they are put onto the 'learning management system' (formally called webct/eLearning). You log in by following the link on the left side bar on myuni - and then look to your individual subjects.
As a heads up, depending on the lecturer, the recording may either be available for streaming or streaming/downloading. Some lecturers refuse to allow lecture recordings to be able to be downloaded (eg. to put on an ipod etc) - they can only be streamed through the site. So if you can't download it, it is likely that is deliberate, and the lecturer will get annoyed with 200 people asking them to allow it to be downloaded and give a very curt response about how you should be attending most lectures anyway (based on past experience lol).
You also can't stream the lectures through safari on an iphone because it requires flash (i tried). Although they were trialling an elearning app last year in some subjects that may allow it to work on apple/mobile devices, but I'm not sure if they are implementing it or not.