Sets the recurrence of the streams global event structure
(PHP 3>= 3.0.13, PHP 4 )
int mcal_event_set_recur_weekly ( intstream, intyear, intmonth, intday, intinterval, intweekdays )
mcal_event_set_recur_weekly() sets the streams
global event structure's recurrence to the given value to be
reoccuring on a weekly basis, ending at the given date.