Exchange 2010 & Installing BES – The unsolvable riddle

Over the last few days I've had the pleasure (2… 3… noot) of installing Blackberry Enterprise Server on our new (6 months old) Exchange 2010 setup at work. Setting up the permissions using the Exchange Command Shell lead me to a problem that drove me absolutely insane. When applying Send-As permissions using the exchange command shell commands that RIM themselves have in their documentation, i hit a brick wall.