How to save the "Package Explorer" in Eclipse

Is it possible, to save the state of the package explorer when closing Eclipse (3.4) and to restore it when opening the workspace again?

By state I mean the nodes (expanded or collapsed).

I am not sure it is possible, but if you have the "Link with editor" button (also presented here) activated, you would open the relevant nodes as soon as you click on of of the editors you left opened (and restored on eclipse restart).

Another way to restore the relevant state is to record some kind of context for a given task:
This is called mylyn