We have an assistant that has full send as permissions for her manager.  Sometimes her manager will create a draft message and have her look it over and send it out as him.  Since last week, anytime the assistant opens a draft message from the managers drafts folder and makes changes and then sends it from him the email does send but when you look at sent items or receive the email it shows being sent from the assistant instead of the manager (not even as on behalf of, it just appears as if the assistant sent the email).  If the assistant creates a new email and changes the from field to the managers name the email sends and appears from the manager, it's only emails that are from the managers draft folder that having issues.

I found a work around of having the assistant move the draft from the managers draft folder to hers and then making the changes and sending as the manager but shouldn't she be able to do this from the managers draft folder?

We are using Exchange 2010, Office 2010, Windows 7.

If she has Send As right she can put her boss's name in the From field, no?