Actually this is not true.  You don't need to open 
your package infront of a "postal authority" as 
long as you bring all the contents back with you 
when you file the claim and hand them over. 
However, EMS claims, I was told must be filed in 
their country of origin and if the package is 
opened, then you can't just mark it "return to 
sender", you have to pay to have it returned.