I think I know what your problem is.
You are using an empty table cell to get a black line.
If a table is not wide enough for the content in it, these empty cells are sometimes reduced to width 0.
I guess the login part of DNN is set quite wide or 100% and therefore "hiding" the border.

I save your page and changed this:

1. Add a class to the table containing the modules
    <table cellpadding="0" cellspacing="0" width="100%" class="bordertable">
(you will have to change this in your skin file,,and remove the extra TD, you have noe for the border)

2. add this to skin.css

.bordertable
    {
    border-right-style:solid;
    border-right-color:#000000;
    border-right-width:4px;
    }

And you should do the same for some of the TD's above...

My saved version looks the way it should now.

Hope this helps

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