I’m not sure I fully understood your question.If you wish to be able to receive and send mail in an Outlook client connected to a Domino server, download and install the free “Outlook Connector for Domino” small utility (just Google for it).
Then, when you will add a new MAPI profile, for your third party app, select the “Additional Server Type” radio button, it will show “Microsoft Office Outlook Connector for IBM Lotus Domino” in the list of extra server types.