function showtpl()
	{
		document.getElementById('template_preview').style.display = "block";
		document.getElementById('template_wait').style.display = "none";
	}
]]>
</script>

[BLOCK preview_site_block]
<br />
<div  id="template_wait">Loading template...</div>
<iframe onload="setTimeout('showtpl()', 3000)" id="template_preview" border="0" src="{preview_site}" style="width: 860px; display: none;"></iframe>

[END preview_site_block]



I was thinking to "hot this up" some... Right now, the iframe just "pops up".
Is it possible (and hard?) to construct the function showtpl(), such that the iframe loads more
"smoothly"? I think i have seen JS solutions for this before, but have no idea how i should do...
Basicly, i want some kind of effect when the iframe is loading, not just as it is now; "popping up after 3 s".

Ideas?