LAST DAY OF MAYAN CALENDAR IS OCT 28, 2011?

http://www.godlikeproductions.com/forum1/message1376143/pg1
Comet Elenin will make it's closest approach to earth at the end of Oct 2011. Many Mayan calendar researchers have said the real end of the Mayan calendar is Oct 28, 2011. According to researchers like Ian Xel Lungold and Dr. Carl Johan Callerman, the true Mayan end date is not Dec.21st, 2012, but Oct.28, 2011. That's a difference of 13 months and three weeks earlier than the more modern or commonly accepted date. Why the difference? The researchers claim that he Dreamspell or 13 lunar-month calender upon which Arguelles and others based their calculations does not take into account the quarterly leap day(Feb.29) introduced into the Gregorian calendar by Pope Gregory in 1582, whereas the true Mayan calendar does. This pushes the end date almost 14 months ahead of schedule to Dec.21st, 2012(as calculated from Aug.of 3115 BC).