[horde] Activesync on Android mail sync

[Roman Gelfand]

I have configured android mail to show mail by conversations.  Activesync
email synced with horde shows one email per conversation (number 1
appearing on each line).  Whereas activesync email synced with exchanged
server shows number of emails in conversation with stacked view.

Is there a setting I need to change on the horde side?

Thanks in advance