Multiple Tables in One - Misalignment - html

Question

EDIT: I did not construct this table myself. A table absolutely shouldn't be constructed this way and is a fix I'm implementing in the future. But the back-end code unfortunately depends on this exact table structure-each inner table has it's own class names and id's and trigger functions, etc.
I've got this problem working with a table made up of multiple tables - One table is the table itself, another table makes up the header, or <thead>, and another table makes up the <tbody>-there are also divs within the table cells (<td>) it looks like this:
<div id="myTableContainer">
<table id="myTable">
<thead>
<table id="myTableHeader">
<tr>
<td>
<div>Header Data 1</div>
</td>
<td>
<div>Header Data 2</div>
</td>
</tr>
</table>
</thead>
<tbody>
<table id="myTableData">
<tr>
<td>
<div>Table Data 1</div>
</td>
<td>
<div>Table Data 2</div>
</td>
</tr>
</table>
</tbody>
</table>
</div>
The problem is that there's some javascript working in the background to resize these table cells based on how much text is in them, but I can't align the header cells with the with the rows below them properly with CSS. I've experimented with the table-layout property and giving each td a max/min-width, but I'm stuck as to getting all the data & columns aligned because if many columns are created, the table gradually mis-aligns. What's more, both the inner tables are generated dynamically, so it's not as simple as restructuring the table as a whole. This table has proved very difficult to work with as it was developed for IE5 or 6 (works in Quirks mode all the way)
Does anyone have any ideas or sure-fire solutions on how to align this table properly? Preferably a CSS-based solution?
If you can't picture it, my table basically looks like this (and gets gradually worse if more columns are inside of it)
I hope I explained this well enough, if more info is needed I will provide

Answer 1

You should not have <table> tags inside <thead> and <tbody>. Your code should just look like this:
<div id="myTableContainer">
<table id="myTable" border="1">
<thead>
<tr>
<td>
<div>Header Data 1</div>
</td>
<td>
<div>Header Data 2</div>
</td>
</tr>
</thead>
<tbody>
<tr>
<td>
<div>Table Data 1</div>
</td>
<td>
<div>Table Data 2</div>
</td>
</tr>
</tbody>
</table>
</div>

Answer 2

I would correct the old code but in case you don't intend to, look for below hack:
I cannot think of a pure CSS solution. But how about CopyCSS (http://upshots.org/javascript/jquery-copy-style-copycss)?
You can call your copyCSS (you can selectively copy only width property). Question is how to detect if width of column changes?
For that you will have to take help of onresize event (http://www.w3schools.com/jsref/event_onresize.asp). For that you have to dynamically add onResize event to at least first row of your second (i.e. inside ) table.