A guy named David Koster found a solution: link
Lightbox and the jQuery menu in SimpleX both use the same variable $. So the solution is to rename the variable the theme uses:
Just edit /wp-content/themes/simplex/header.php by replacing the first by the second text mentioned below.
$(function(){
var tabContainers = $(’div#maintabdiv > div’);
tabContainers.hide().filter(’#comments’).show();$(’div#maintabdiv ul#tabnav a’).click(function () {
tabContainers.hide();
tabContainers.filter(this.hash).show();
$(’div#maintabdiv ul#tabnav a’).removeClass(’current’);
$(this).addClass(’current’);
return false;
}).filter(’#comments’).click();});
Rename the variable (in this example with mjq):
mjq(function(){
var tabContainers = mjq(’div#maintabdiv > div’);
tabContainers.hide().filter(’#comments’).show();mjq(’div#maintabdiv ul#tabnav a’).click(function () {
tabContainers.hide();
tabContainers.filter(this.hash).show();
mjq(’div#maintabdiv ul#tabnav a’).removeClass(’current’);
mjq(this).addClass(’current’);
return false;
}).filter(’#comments’).click();});
The only thing left to do is telling the jQuery SimpleX uses to not look for $ but for mjq. Therefore edit /wp-content/themes/simplex/js/jquery-1.2.6.min.js (or similar) replace the following:
var _jQuery=window.jQuery,_$=window.$;
becomes: var _jQuery=window.jQuery,_mjq=window.mjq;
var jQuery=window.jQuery=window.$=function(selector,context)
becomes: var jQuery=window.jQuery=window.mjq=function(selector,context)
window.$=_$;
becomes: window.mjq=_mjq;