(PHP 5.5.0, PECL >= 3.0.0a1)
IntlCalendar::setSkippedWallTimeOption — Set behavior for handling skipped wall times at positive timezone offset transitions
Object oriented style
$wallTimeOption
   )Procedural style
   Sets the current strategy for dealing with wall times that are skipped
   whenever the clock is forwarded during dailight saving time start transitions.
   The default value is IntlCalendar::WALLTIME_LAST (take
   it as being the same instant as the one when the wall time is one hour
   more).  Alternative values are
   IntlCalendar::WALLTIME_FIRST (same instant as the one
   with a wall time of one hour less) and
   IntlCalendar::WALLTIME_NEXT_VALID (same instant as
   when DST begins).
  
This affects only the instant represented by the calendar (as reported by IntlCalendar::getTime()), the field values will not be rewritten accordingly.
The calendar must be lenient for this option to have any effect, otherwise attempting to set a non-existing time will cause an error.
This function requires ICU 4.9 or later.
calThe IntlCalendar resource.
wallTimeOption
      One of the constants IntlCalendar::WALLTIME_FIRST,
      IntlCalendar::WALLTIME_LAST or
      IntlCalendar::WALLTIME_NEXT_VALID.     
     
   Returns TRUE on success. Failure can only happen due to invalid parameters.
  
See the example on IntlCalendar::getSkippedWallTimeOption().