President’s Assent Received: 17th September 1974
An Act to amend the Constitution of the Islamic Republic of Pakistan [Gazette of Pakistan, Extraordinary, Part I, 21st September, 1974]

The following Act of Parliament received the assent of the President on 17th September 1974, and is hereby published for general information:


An Act further to amend the Constitution of the Islamic Republic of Pakistan

Whereas it is expedient further to amend the Constitution of the Islamic Republic of Pakistan for the purposes hereinafter appearing;

It is hereby enacted as follows:

1Short title and commencement
(1)This act may be called the Constitution (Second Amendment) Act, 1974. 
(2)It shall come into force at once.
2Amendment of Article 106 of the Constitution.
In the Constitution of the Islamic Republic of Pakistan hereinafter referred to as the Constitution, in Article 106, in clause (3), after the words “communities” the words and brackets “and persons of Quadiani group or the Lahori group (who call themselves ‘Ahmadis’)” shall be inserted.
3Amendment of Article 260 of the Constitution.
In the Constitution, in Article 260, after clause (2) the following new clause shall be added, namely–
(3)A person who does not believe in the absolute and unqualified finality of The Prophethood of MUHAMMAD (Peace be upon him), the last of the Prophets or claims to be a Prophet, in any sense of the word or of any description whatsoever, after MUHAMMAD (Peace be upon him), or recognizes such a claimant as a Prophet or religious reformer, is not a Muslim for the purposes of the Constitution or law.


http://www.pakistani.org/pakistan/constitution/amendments/2amendment.html