Anyone on here know anything about Google Apps?:

I'd like to know if there is a way of having two domains within one google apps instance. Specifically I have a .com domain already working for my email, but want to add .com.au to the same Google Apps instance so I can manage aliases etc. I'd prefer not to have to create a new Google App's instance for the .com.au and then have to redirect .com.au emails to .com

Also:

Is a way of adding a 'global signature' to google apps/gmail email's. This so all user's email addresses get it apended at the end. i.e. for creating a disclaimer!

I've had a look around the google forums and can't seem to find a way, so thought I'd ask here

TIA