thank you. I think I might have now understood the problem.
In the enclosed example I made two object: a StaticProducer and (two instance of) a Static Receiver. They both refer to MyStaticVar.
In order to update the changes I made in the code (with Eclipse) I usually clear the patch and than I recover it using cmd-z.
If you do you so after a change in StaticProducer or MyStaticVar there is no problem. On the other hand, if you do you make any change in Static Receiver, and even if you close and re-open the patch, the Static Receiver will be null! If you close and re-open Max… it works!
Am I missing something?