Send / Forward Icon Not Appearing after replying to email

We have Domain Exchange Server 2010 setup.  We have email groups that people share responsibility to replying to customer emails.  On all windows clients running all versions of Outlook 2007, 2010 and 2013 when replying to email a reply or forward icon arrow will appear and viewable by Windows and MAC clients in the shared email group mail.  If a reply or forward is done from the MAC from the email group no arrow ICON appears on either Windows or MAC clients.  However, when replying to personal emails on personal email boxes a ICON will appear replying or forwarding messages.  We primarily use Outlook 2011 for MACs and I've even tested this using the Apple Client email built into the system with the same results.  This problem seems to be specific to MAC clients only.  Having these arrow ICONs appear is important so we don't have agents working on the same emails over and over again.  Agents do have full permissions and send permissions for these email accounts on the Exchange server.  I've seen this a various versions of MAC OS's.  The version I been using for testing is 10.8.5.  Has anyone experience this issue and is there a fix for this?