I've got an interesting one... I've been trying to setup a generic account (i.e. firstname.lastname@example.org) so that others have "Send As" permissions to it. This is different from "Send on behalf of". The latter puts the name of the sender in the "From" field, i.e. from "Bob Smith on behalf of email@example.com". This is not what I want. I want another user to be able to send a message directly as "firstname.lastname@example.org," which should be possible by assigning "Send As" permissions. However, I've got a problem... Inside of Active Directory Users and Computers, with the advanced features turned on (under the View menu), I open the email@example.com account, click on the Exchange Advanced tab, click Mailbox Rights and neither "Send As" or "Receive As" is listed as an option (not listed under the Advanced button either). The only entries I have are:
Delete Mailbox Storage
Full Mailbox Access (I do NOT have this patch installed - http://support.microsoft.com/kb/895949/
Associated External Account
Another article that best describes my problem is: http://www.smallbizserver.net/Default.aspx?tabid=53&forumid=5&postid=6019&view=topic
except this user had the Send As and Receive As options.