Support only sends emails to the primary email address. The secondary email addresses are only used to identify user accounts, but outgoing email ticket updates are only sent to the primary email address.

This system behavior has two negative consequences:
a) The requester email address of the incoming mail is always the primary email address, although it was originally sent by one of the additional mail addresses of that end user profile.

b) If an end user has more than one email address, you never can send a ticket reply (CC) to one of the additional email addresses of that end user.

A lot of our users have two or more email addresses and would like to receive replies from Support to all of there email addresses (esp. in times they work from home).