Update here:http://jsfiddle.net/5ej8G/3/ (code is also pasted below)

Main suggestions:

• your exportSymbol function can be refactored to handle an array of publicPaths and Objects.
• The subscribe conditions can be consolidated since they throw the same message.
• check your parameters before using. typeOf checks don't work well with all objects, but there are techniques to have them work with all objects. One from Angus Croll(http://javascriptweblog.wordpress.com/2011/08/08/fixing-the-javascript-typeof-operator/) is included in the link above.
• Explicitly state which elements you want your code to act on, maybe by passing in a parameter object. doing a $("*"), on medium to large pages (with lots of dom elements) can be a performance hit.

(function (window, $, undefined) {    "use strict";    var ab = window.ab = window.autoBinder = {},        elements,        toType = function(obj) {      return ({}).toString.call(obj).match(/\s([a-zA-Z]+)/)[1].toLowerCase()    };    //can handle an array of publicPaths and objects    ab.exportSymbols = function (paramArray) {        var tokens,            target = window,            i,            index,            len,            limit,            exportSymbol;        if(toType(paramArray) !== 'array') {             throw "You must pass an array into this function.";                    }        //Export Symbol now becomes a inner helper function        exportSymbol = function(pubPath, obj) {            tokens = pubPath.split(".");            lastIndex = tokens.Length;            for (i = 0; i < lastIndex ; i++) {                target = target[tokens[i]];            }            target[tokens[lastIndex]] = obj;        };        //validate and run helper function on each object in array        for(index= 0, len=paramArray.length; i < len; i++) {            if(toType(paramArray.publicPath) !== 'string'                || toType(paramArray.publicPath) !== 'object') {                    continue;            }            exportSymbol(paramArray[index].publicPath, paramArray[index].obj);                    }    };    ab.exportProperty = function (owner, publicName, object) {        owner[publicName] = object;    };    ab.extensions = function () {        return {            datePicker: function (element) {                var params = {                    minDate: 0,                    showButtonPanel: false                },            e = $(element);                if (e.data("mindate") !== undefined) {                    params.minDate = e.data("mindate");                }                if (e.data("showpanel") !== undefined) {                    params.showButtonPanel = e.data("showpanel");                }                e.datepicker(params);            }        };    }();    ab.hookups = (function () {        return {            make: function (value, element) {                if (ab.extensions[value]) {                    ab.extensions[value](element);                }            },            publish: function (value, $element) {                if (!value) {                    return;                }                $element.change(function () {                    $element.trigger(value, $element);                });            },            subscribe: function (value, $element) {                var trigger = $element.data("trigger");               //Conditions can be consolidate since they trow the same message                if ((trigger === undefined) || !ab.extensions[trigger]) {                    throw "Found Subscribe without Trigger.";                }                                $(document).bind(value, function (event, htmlElement) {                    ab.extensions[trigger](event, htmlElement, $element);                });            }        };    })();    //can pass in a an array of object instead of mutiple calls    ab.exportSymbols([                     {pubPath : "ab.extensions.datePicker", obj : ab.extensions.datePicker},                     {pubPath : "ab.hookups.make"         , obj : ab.hookups.make},                     {pubPath : "ab.hookups.publish"      , obj : ab.hookups.publish},                     {pubPath : "ab.hookups.subscribe"    , obj : ab.hookups.subscribe}    ]);    $(window).load(function () {        elements = $("*").filter(function () {            var data = $(this).data(),                p;            if (data === undefined) {                return false;            }            for (p in data) {                if (data.hasOwnProperty(p)) {                    return true;                }            }            return false;        });        elements.each(function () {            var obj = $(this),                data = obj.data(),                p;            for (p in data) {                if (data.hasOwnProperty(p)) {                    if (ab.hookups[p]) {                        ab.hookups[p](data[p], obj);                    }                }            }        });    });} (window, jQuery));//  Example Extending extensions    window.ab.extensions.effectiveDateChanged = function (event, triggerElement, subscribedElement) {        var $element = jQuery(triggerElement);        subscribedElement.val("Value set to: " + $element.val());    };window.ab.extensions.dropDownChanged = function(event, triggerElement, subscribedElement) {    var $element = jQuery(triggerElement),        value = $element.val();    if (value === "") {        subscribedElement.attr("disabled", "disabled");        subscribedElement.html("");        return;    }    subscribedElement.removeAttr("disabled");    subscribedElement.html("<option>" + value + "</option>");};

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