$.ajax, $.post, $.get - not working

$.ajax, $.post, $.get - not working

Hi everyone! I'm pretty new to jQuery and while trying to use some AJAX in my .js files I get nothing. I have index.php which includes 3 files(jquery.js and jquery-1.5.min.js and json.js) from js folder at the same level with index.php I have saveXML.php file. All I need to do is to send some data from index.php(from a template wich loads there) to saveXML.php(which should create .xml file, but this is not important). My jQuery code is as follows:
jQuery('#saveXML').click(function() {
  jQuerymarking = jQuery('#product__product__object_edit_articul').attr('value');
  jQuery('#markingHidden').attr('value', jQuerymarking);
  jQuery.post('saveXML.php', ('#saveXMLform').serialize(), function(data) {
    jQuery('#result').html(data);
    jQuery('#result').removeClass('hidden');
  }); 
});
It just have no effect, just nothing. I tried everything, I tried different examples from this site and still no result. So, I have two questions:
1) Can there be some problem on the server-side(this is not a localhost)? If yes, what problems?
2) Maybe I have done something stupid? I spent 5 hours today, but no solution.