(a) who has entered into or contracted a marriage with a person having a spouse living; or
(b) who, having a spouse living, has entered into or contracted marriage with any other person, shall be eligible for appointment to the said posts:
Provided that the Central Government may, if satisfied, that such marriage is permissible under the personal law applicable to such persons and the other party to the marriage and that there are other grounds for so doing, exempt any person from the operation of this rule.