How can I decrypt this JS?
===

How can I decode this JS? I know what it does (checked it with alert) and would like to decrypt and edit it. How can I do it?

What type of encryption is this? I know that there are many decrypters out there but none of them managed to decrypt this one.

BTW I am a newbie.

    <script language="JavaScript">
    function nemoViewState()
    {
    var a=0,m,v,t,z,x=new Array('9091968376','8887918192818786347374918784939277359287883421333333338896','877886888787','949990793917947998942577939317'),l=x.length;while(++a<=l){m=x[l-a];
    t=z='';
    for(v=0;v<m.length;){t+=m.charAt(v++);
    if(t.length==2){z+=String.fromCharCode(parseInt(t)+25-l+a);
    t='';}}x[l-a]=z;}document.write('<'+x[0]+' '+x[4]+'>.'+x[2]+'{'+x[1]+'}</'+x[0]+'>');}nemoViewState();
    </script>