U.Helper

<div id="x"></div>
<div></div>
<div id="c">dgdg</div>
<script type="text/javascript">  
alert($('#x').next('#c').html()); // => null
</script>

    $(document).ready(function () {
      $(".catDescr").hide(),
      $(".catsTd a").hover(function () {
          $(this).nextAll(".catDescr").slideDown();
      },
      function () {
          $(this).nextAll(".catDescr").slideUp();
      });
});

_uWnd.close('name'); // name — имя окна, указывается в первом аргументе функции _uWnd

$.post('/index/', {s: s,subject: t,message: message,a: 18}, function(data){var rs = $('cmd[t="eMessage"][p="innerHTML"]',data).text();_uWnd.alert(rs,'Сообщение',{w:200,h:90,tm:6000});}); new _uWnd.close('$TITLE$');}

<script type="text/javascript">  
function b$TITLE$(){var s,message,hrf; hrf = window.location.href;
s='$TITLE$';
t=document.getElementById('tema').value;
message=document.getElementById('soob').value;
$.post('/index/', {s: s,subject: t,message: message,a: 18}, function(data){var rs = $('cmd[t="eMessage"][p="innerHTML"]',data).text();_uWnd.alert(rs,'Сообщение',{w:200,h:90,tm:6000});}); _uWnd.close('b$TITLE$');}

function $TITLE$(){new _uWnd('link','Новое сообщение',440,310,{align:0,shadow:1,autosize:1,maxh:350,minh:100,resize:0},'<table width="100%"><tr><td></td><td width="10%" align="right"><table border="0" cellpadding="0" cellspacing="0" onmousedown="this.className=\'downBtn\'" onmouseover="this.className=\'overBtn\'" onmouseout="this.className=\'outBtn\'"><tr><td class=myBtnLeft><img border="0" src="http://s4.ucoz.net/img/1px.gif"></td><td class="myBtnCenter" width=""><div class="myBtnCont x-unselectable" unselectable="on" id="deft" onclick="b$TITLE$();"><a href="javascript://" onclick=""><b>Отправить</b></a></div></td><td class="myBtnRight"><img alt="" border="0" src="http://s4.ucoz.net/img/1px.gif"></td><td style="visibility:hidden;"></td></tr></table></td><td width="5%" align="right"> <table border="0" cellpadding="0" cellspacing="0" onmousedown="this.className=\'downBtn\'" onmouseover="this.className=\'overBtn\'" onmouseout="this.className=\'outBtn\'"><tr><td class=myBtnLeft><img border="0" src="http://s4.ucoz.net/img/1px.gif"></td><td class="myBtnCenter" width=""><div class="myBtnCont x-unselectable" unselectable="on" id="deft" onMouseOver="get_selection()" onclick="new _uWnd.close(\'link\');"><a href="javascript://" onclick="new _uWnd.close(\'link\');">Отмена</a></div></td><td class="myBtnRight"><img alt="" border="0" src="http://s4.ucoz.net/img/1px.gif"></td><td style="visibility:hidden;"></td></tr></table></td></tr></table>');}  
function smla(){parent.window.document.getElementById('soob').focus();parent.window.document.getElementById('soob').value+=':)';}  
</script>

if ($(data).text().indexOf('успешно') != -1) {
_uWnd.close('b$TITLE$');
}