I was able to acheive this by updating the javascript in jHtmlArea-0.7.5.js
Particularly, the following:
...
updateTextArea: function () {
this.textarea.val(this.toHtmlString());
//Add the following javascript
var val = $(this.textarea).val();
var vallength = val.length;
$("#counter-div").html(vallength);
},...
Then you will able to use <div id="counter-div"></div>
right under your textarea.
There will be some additional modifications if you want to have multiple jHtmlAreas on a single page. Basically counter-div
will need to be uniquely identified to the textarea you are modifying.