Possible to pull contacts from custom modules for Contact Roles in Deals?

Possible to pull contacts from custom modules for Contact Roles in Deals?

I would like to add contacts to the Contact Roles section in Deals, but the contacts are in a custom module that I created. When I go to Add Contact Roles to the Deal I can only select contacts from the Contacts module. I've been unable to find a setting that allows me to map from a different module. Is that possible?