Come to think of it, while we're on the subject, here's my problem:
iTunes (v6.0.4) is open and playing music as usual. I run Mail or Firefox or some other app. When I go back via the Apple\Recent Item menu item, the iTunes menu appears (or not) and there is no iTunes window. I am then forced to use the Force Quit manouvre on iTunes. Why is this happening? What cause this behaviour?