Problem with this scroller javascript.

[lynxus]

Hi guys , I have this:

This basically just keeps a div scrolled to the bottom all the time.

 

My question is..

How can i do it so it would ONLY run if the scrollbar is currently at the bottom.

IE:

 

If (scrollbar == bottom) {

    runscript;

  }else{

  dont

}

 

What i want to achieve is this script will only run if the user has scrolled to the bottom , if they were to scroll up again it wouldnt run ( until they bring the scrollbar back to the bottom )

<script language="javascript" type="text/javascript">

function scroller(){
var objDiv = document.getElementById("sessiontext");
objDiv.scrollTop = objDiv.scrollHeight;
}
</script>

 

Many thanks for looking

-G