stack option for a draggable div on jquery-ui 1.9.2 resets the element z-index

[Jaky]

I have several (dinamically generated) divs, whose z-index is set in css to 120:\[code\].plugin { position: absolute; z-index: 120; }\[/code\]They contain a title (positioned on the top) and a canvas:\[code\].plugin_title { font-size: 13px; color: rgba(255, 255, 255, 0.9); font-family: arial; background-color: #300; z-index: 150; }.plugin_canvas { position: relative; background-color: black; border: 1px solid #300; border-bottom-right-radius: 5px; z-index: 120; }\[/code\]When I create them, I do:\[code\]var div = $( '<div class="plugin ' + audioclass + '" id="'+ id + '"</div>').width(width + 2).height(height + 2);var ctx = $( '<canvas class="plugin_canvas" width="' + width + '" height="'+ height + '" />', {width: width, height: height} );var title = $( '<div class="plugin_title"> ' +name + ' </div>');title.appendTo(div);ctx.appendTo(div);div.appendTo('#plugin_area');\[/code\]Then call \[code\]jsplumb.draggable\[/code\] to make them draggable (jsplumb just calls jquery's \[code\].draggable()\[/code\])\[code\]jsPlumb.draggable(div, {cursor: "move", handle: title, opacity: 0.9, stack: ".plugin", scroll: true})\[/code\]The problem is that when I drag one of the .plugin divs, its z-index is reset to 1 (and incremented each time I drag it, because of the \[code\]stack\[/code\] option). Instead, I want the z-index to start from 120 (the original z-index value for the .plugin divs) and be incremented from that value.jqueryui 1.7 had a \[code\]min\[/code\] parameter for the \[code\]stack\[/code\] option. In jqueryui 1.9.2 (the version I'm using), you can only specify a selector, and, from which I can understand, the stacking should start from the pre-existent z-index of the element. Instead, it seems arbitrarily re-starting at 1. What am I missing?(jsplumb: 1.3.16, jqueryui: 1.9.2, jquery: 1.8.1. Please note I can't roll back to an older version of jquery-ui)