Company email Privacy? Not so much.
When it comes to sending email from your employers company email address, there is no such thing as privacy. Company email users need to be reminded of this. It should start with an Acceptable Use Policy (AUP) that is signed upon employment and then employees need to be reminded of this through training or occasional memos.
Many people do not understand that any email communication via a company email account is company property. These message are typically stored in a long term archive and can be recalled upon by court order in a legal case. It could be a law suit with a client, competitor, employment, sex harassment etc. Any email that is even remotely related to the case can be presented as evidence. As a result, employees need to be trained to think about every email message that they compose.
These policies and training many times falls in the hands of your IT department... we get to be the bad guys... again! It's no wonder that they hate us.