I successfully set up an iPod Touch to use Zimbra Mobile (ActiveSync). However, when I reply to a message on the iPod Touch it doesn't mark the original message with the little "replied-to" icon in Zimbra Desktop or in the Zimbra web client. I checked my sent messages folder and the email I sent from the iPod shows up there, so I know it got sent. It's just the little indication that the message was replied to that's missing.
Any ideas what causes this little glitch?