error with tbl.tBodies[0].rows.length

hai, i’m new with javascript..

i want to make a dinamic table using javascript. i got the folowing code (i’m not posting all the lines..)

function addRowToTable(num){
var tblName = ‘listKPI’;
window.alert(‘here 1 : +tblName);
var tbl = document.getElementById(tblName);
window.alert(‘here 2’);
var nextRow = tbl.tBodies[0].rows.length;
window.alert(‘here 3 :’ + nextRow);
//and so on…
}

here are the html lines for the table:

<table id=”listKPI” cellpadding=0 cellspacing=0 border=1 align=”center”>
<thead>
<tr>
<td>&nbsp No. &nbsp</td>
<td>&nbsp choose &nbsp</td>
<td>&nbsp KPI Name &nbsp</td>
<td>&nbsp Owner &nbsp</td>
</tr>
</thead>
<tbody>
</tbody>
</table>

? and here’s the prooblem : the javascript lines work fine in my other pages but in this page, the function doesn’t work. the “here 1” and “here 2” show up without any problem. but “here 3” never shows up. i use IE7 (i wonder if it has something to do with the problem).

and there’s no error message shown anywhere in the browser.. ?

anyone know the posibilities of the cause of the error?

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