A system, method and computer program product are provided for supporting Transactional Memory communications. In one embodiment, the system comprises a transactional memory host with a host transactional memory buffer, an endpoint device, a transactional memory buffer associated with the endpoint device, and a communication path connecting the endpoint device and host. Input/Output transactions associated with the endpoint device executed in transactional memory on the host are stored in both the host transactional memory buffer and the transactional memory buffer associated with the endpoint device. In an embodiment, the Transactional Memory system further comprises an intermediate device located on the communication path between the host and the endpoint device, and an intermediate transactional memory buffer associated with said intermediate devices. In this embodiment, the Input/Output transactions associated with said endpoint device are stored in the intermediate transactional memory buffer associated with the intermediate device.