Section 6A. Under the supervision of the commissioner, superintendents of hospitals under the control and supervision of the department may establish programs for the training of residents in medicine, and in such other specialties and subspecialties of medicine as he may deem necessary. The persons undergoing such training shall be designated as fellows and shall be eligible for training grants from the commonwealth, which grants shall be exempt from the provisions of chapter sixty-two. Recipients of said grants shall not be subject to the provisions of chapter thirty-one and shall not be deemed to be employees of the commonwealth. Approval of said training program by the personnel administrator shall be required in accordance with the provisions of section twenty-eight of chapter seven.