I remember these kinds of documents. Before the era of blogging they were available on Microsoft’s internal systems or brought to you by your local Microsoft consultant. Now you get all this great information for free, useful for security-oriented organizations and these day all medium-sized to large companies need to be.
Read it here:
http://msexchangeteam.com/archive/2006/08/29/428781.aspx
Next on the blog: permissions required for snakes to be on a plane