Detect IE6

Detect IE6

Hello,

First of, im new here. I'm not native english speaking. If i make spellingmistakes or so, for that i am sorry.
Anyway I'm into jquery for a few weeks now, mainly i'm just programming in css/php/xhtml and some xml but jquery is too populair not to know some tricks about it. So i did some reading/tutorials/ modified e.g a picture-plugin etc.

Anyway, i'm building a website that uses transparant PNG's all over the place. No problem for all the recent webbrowsers. But i did some research and noticed that 17% still uses IE6, wich, sadly does not support transparant PNG's.

TO THE POINT, THE ACTUAL QUESTION
I would like to have a check that when the user if actualy using IE6 he gets only 1 div with the message, please upgrade your browser and an url to that update. I could do something like


$(document).ready(function(){
  if($.browser.msie6){
     alert("Do stuff")
  } });


I know its not entirely correct, but you get what i mean. It would just give an alertbox but you would still see the entyre site. What i want is that is shows just 1 div with my desired text, and hides the entire site

How would i do this ?

Hopefully someone can help me out.

Thanks in advance