[jQuery] parentNode is null or not an object

I am getting this error on IE8; it is working nice on firefox, and I
have to support IE.

I found this page:
http://www.nabble.com/Error-with-BlockUI:-%27parentNode%27-is-null-or-not-an-object-td22990094s27240.html

And they identify as the problem occurring here:

The error occurs in the 'install' function right here:

<quote from link>
var node = msg.jquery ? msg[0] : msg;
var data = {};
$(el).data('blockUI.history', data);
data.el = node;
data.parent = node.parentNode; <--- ERROR OCCURS HERE
</quote from link>

Where it talks the problem, and I believe I have run into the same
error. The problem is that I can't figure out what I am supposed to do
to fix it :)

Any pointers on how to fix this so that blockUI can work nicely with
IE?