Miss. Code Ann. § 73-13-33

All professional engineers, licensed in accordance with the provisions of Chapter 56 of the Laws of Mississippi of 1928, Extraordinary Session, and as amended under Senate Bill No. 383, Chapter 131, Laws of 1940, and whose certificates of licensure are in effect at the time of passage of Sections 73-13-1 through 73-13-45, shall be entitled to all the rights and privileges of a licensed professional engineer as provided for in those sections, while the said certificate remains unrevoked or unexpired.