The term "wages" shall not include the payment by an employing unit (without deduction from the remuneration of the individual in its employ) of the tax imposed upon an individual in employment under section 1400 of the federal internal revenue code, as amended, or any amount paid to a person in the military service for any pay period during which he or she performs no service for the employer: PROVIDED, HOWEVER, That prior to January 1, 1952, the term "wages" shall not include dismissal payments which an employing unit is not legally required to make.