[Andrew111888]

You should probably use some javascript to preload the images as they blink for a second before the mouseover image loads.

<script type="text/javascript">
<!--
preload_images('images/smoothblue/nav_chat_on.gif', 'images/smoothblue/nav_home_on.gif', 'images/smoothblue/nav_forum_on.gif');
-->
</script>

I don't think it's necessary, but I preload the images that the mouseover replaces as well (non _on images).