I use SWFObject not in a snippet without any problems in IE6.
I just reference the file in the <head> section and have:
<div id="tvadHead">
<a href="http://www.adobe.com/go/getflashplayer">
<img src="http://www.adobe.com/images/shared/download_buttons/get_flash_player.gif" alt="Get Adobe Flash player" />
</a>
</div>
<script type="text/javascript">
var fo = new SWFObject("assets/flash/crickwebad.swf", "tvadHead", "468", "60", "8", "#FFFFFF");
fo.addVariable("variable", "varvalue");
fo.write("tvadHead");
</script>
</div>
In the body.
The actual code is after the div in which the flash banner appears.