Yes, you will need to add the domain making these requests to the appropriate list in your Luminate Online configuration:
  1. Log in to Luminate Online as an administrator.
  2. Go to Setup | Site Options. Click the tab labeled "Open API Configuration."
  3. Click the link labeled "Edit Javascript/Flash configuration."
  4. Add your domain to the "Allow JavaScript/Flash API from these domains" to simply create new constituents or to the "Trust JavaScript/Flash API from these domains" to retrieve and update constituent data.