Propper manners are when nation's president is speaking sit down quietly and listens to his statements -
I think Mr Zardari is with in his rights to silece the screemer at rally -
its a speech he is giving its not a 1 on 1 debate with the critic in audiance , highly unprofessional behavior by the crictic
Also there should be more controlled speeches like they do in USA where all the questions are pre-screened and approved prior to any national speech