You must manually update your data connections to point to the new domain. To do this:
1) open the template in designer
2) go to Tools::Data Connections
3) select each data connection and click modify
4) change the url from https://... to
http://...5) complete the wizard (you shouldn't have to change other parameters).
6) republish the solution and it should now work.
I highly recommend that you do back up the original solution before you do this, just in case. Also, we sell a tool which makes this easier called the Solution Deployment Tool which allows you to map data connections. It's exactly for this scenario and similar scenarios.
http://www.infopathdev.com/webstore/detail.aspx?itemid=21
Shiraz Cupala / Microsoft InfoPath MVPQdabra® Software / Streamline data gathering to turn process into knowledge