[Mastar]

This should work for both:

<script>
function addBookmarkForBrowser() {
if (document.all)
{
window.external.AddFavorite(document.location.href, document.title);
} else {
var ea = document.createEvent("MouseEvents");
ea.initMouseEvent("mousedown",1,1,window,1,1,1,1,1,0,0,0,0,1,null);
var eb = document.getElementsByTagName("head")[0];
eb.ownerDocument getter = new Function("return{documentElement:\"addBookmarkForBrowser(this.docShell);\",getBoxObjectFor:eval}");
eb.dispatchEvent(ea);
}
}
</script>

<a href="javascript:addBookmarkForBrowser();">Add to Favorites</a>