I've had an email from someone already in my kids' the address book go into the mail approval queue. I'm not positive that it is due to capitalization differences between the from address in the header of the message and the contact book, but it is my best guess as to why it failed. If this is indeed the case, I realize that strictly according to the RFCs, the local part of an email address IS case sensitive, I've never actually seen anyone allow
[email protected] and
[email protected] as separate email addresses.
I'd suggest either making the comparison case insensitive or making it a user preference (especially since you can't enter multiple addresses per person in the contact book)