What is this code for ?

I created a website for a client and added a live chat from live2support.com . When I insert the code for the chat function all of my menu links stopped working. Tech support for live2support informed me that a piece of my code was the problem. Here is the code they said needed correcting.

<!--[if lt IE 7]><script type="text/javascript" src="index_htm_files/png.js"></script><![endif]-->
<script type="text/javascript">xr_aeh()</script>


And this is correction they said needed to be made.

<!--[if lt IE 7]><script type="text/javascript" src="index_htm_files/png.js"></script>
<script type="text/javascript">xr_aeh()</script><![endif]-->

So all the problem was is the <![endif]--> needed to be moved to the end of the string. Thats fine, I edited that on my server on each page and everything works great.

Here is my question, Im not a code person so Im trying to figure out what that code is for and why it was wrong to begin with. Im a WYSWYG designer so I don't know if its something I can do differently in the Xara part. Because now if I make any updates to the site I will have to go into my server each time and change the code again.

I was hoping someone would have chimed in by now. But alas.

I'll see if I can get someone at Xara to have a look at this and give you an answer.

<!--[if lt IE 7]><script type="text/javascript" src="index_htm_files/png.js"></script><![endif]-->
That line of code will not execute unless the browser is IE6 or older. What it does is enable older versions of IE to work with a .png image.

<script type="text/javascript">xr_aeh()</script>
That line of code is to be executed any time it is encounted on the page.

What was recommended by live2support is to hide that second line and only execute if the browser is IE6 or older.

Only the Xara developers can say if that will make things work correctly or not.

Xara is looking into this and should respond in the next day or two.

The xr_aeh() function initiates variables used by the Xara generated scripts such as rollover effects, photo pop-ups, menus etc. It also applies some workarounds for browser compatibility issues. This function must be executed in all browsers in order to make sure that all our effects work correctly. As Soquili correctly noted, the recommendation from live2support results in this function being ignored in all browsers except for the IE6 and older versions. This may result in unpredictable issues with our built-in features. However, it may not be apparent instantly, and in some cases, depending on what exactly features you have on your page, it may still work well.

Thanks John.