You should NOT disable group-chat history, you should specify that you does not want to receive history, as described in XEP-0045:
<presence
from='hag66@shakespeare.lit/pda'
id='n13mt3l'
to='coven@chat.shakespeare.lit/thirdwitch'>
<x xmlns='http://jabber.org/protocol/muc'>
<history maxchars='0'/>
</x>
</presence>
Your XMPP library should be able to specify "maxchars" or "maxstanzas" or "seconds" property of the room joining packet.