Q about packages in class diagrams

Hi all,

In my main class diagram, I've placed two packages: package1 and  
package2.

Then, under package1 in the package-centric view (on the lefthand  
side of the workspace), I've put another class diagram with classes  
that are in package1. I've done the same with package2.

Now, I have a class in package1 that is extended from a class in  
package2. How do I draw that? If I try to draw the extends  
relationship, I immediately get a new class...

Thanks,

--Rob