Why is the calendar not working?

Question

CMS

Riddle (they love riddles right there? :D )

there is a page gtrk-kurgan.ru/index.php?option=com_content&view=section&layout=blog&id=2&Itemid=14 - there is a calendar from the bottom left where you can poke the months left and right. And there is a page gtrk-kurgan.ru/index.php?option=com_content&view=article&id=2931&catid=10&Itemid=22 , there is a calendar on the right, but the months do not poke back and forth. The server part of the calendars is the same, the options are the same (in fact, you can see by Firebug that AJAX responses come alone), the HTML code is also the same. The question is - why are the months poked in one, but not in the second?

PS if anything, the answer is known, I'm not to help me. Just to think a little.

Answer 1

On a page with a working calendar, the variable $ refers to mootools, where the calendar does not work $ - jQuery.
It's kind of lazy to dig further.

Answer 2

When I click on the arrows, the firebug says this:
$(this.options.update).empty().set is not a function

Answer 3

Wuron: Well done. The problem is that mootools and jquery do not allow each other to work. More precisely, in this case, jQuery does not allow mootools to work from the calendar.