How to draw a line between draggable and droppable?

I'm using the excellent JQuery UI to do a "mapping" so the user can "map" persons from one program to persons from other program.

using this simple JQuery:

$(document).ready(function() {
    $("div .draggable").draggable({
        revert: 'valid',
        snap: false
    });

    $("div .droppable").droppable({
        hoverClass: 'ui-state-hover',
        helper: 'clone',
        cursor: 'move',
        drop: function(event, ui) {
            $(this)
                .addClass('ui-state-highlight')
                .find("img")
                .removeAttr("src")
                .attr("src", "_assets/img/icons/check-user-48x48.png");

            $(this).droppable('disable');

            $(ui.draggable)
                .addClass('ui-state-highlight')
                .find("img")
                .removeAttr("src")
                .attr("src", "_assets/img/icons/check-user-48x48.png");

            $(ui.draggable).draggable('disable');
        }
    });

    $("div .droppable").bind("dblclick", function() {
        $(this)
            .removeClass('ui-state-highlight')
            .find("img")
            .removeAttr("src")
            .attr("src", "_assets/img/icons/user-48x48.png");
        $(this).droppable('enable');

        EnableSource($(this));
    });
});

I get to this:

what I really wanted was (if possible) create a line between Elsa and Kjell so it makes the connection between them clear.

I can always do it with numbers inside the boxes, but I really wanted to know how to do this using the lines.

Thanks.

• updated (08.Jul.2013) Updated with latest versions of libraries; html refactored using JsRender;
• updated (29.Sep.2011) Added GIT Repo; cleaned the code; update to latest framework versions;
• updated (03.Mar.2013) Fixed links with working example;

Current example uses:

• HTML 5 doctype
• jQuery v.1.10.2
• jQuery UI v.1.10.3
• Raphael v.2.0.1
• JsRender v.1pre35 (optional, used for HTML simplification)

Source

> Source code in Git Repository

Demo

> Page demo at JSBIN

---

Works on FF, IE, Chrome, Safari and Opera.

tested on:

• Firefox 6 and 7 .. 22
• IE 8 and 9 .. 10
• Chrome 12+ .. 27
• Safari 5+ .. 6
• Opera 11.51 .. 15

to show you all, I just made a little demo of my accomplishment (I am a proud person today!):

> Video demo

and a little image:

I'm too new to post a link but if you google "Library for simple drawing with jQuery", you may find what you're looking for. :)

link here