Manager's on commission for player sales

I read that Harry Redknapp was on either 5% or 10% commission for player sales whilst at Portsmouth.

Is this normal ? I remember reading about Mike Newell at Luton and he was on a similar deal.

This doesn't sit well with me, Imagine Dave Jones having a such a deal? Half a million in his pocket for Ramsey, couple hundred grand for Roger Johnson. Nice earner if you can get it....

if thats true didnt harry rednapp sell montari to real madrid for something like 18 million!! if that the case....................