HTML___中數據過長自動換行問題﹗

如下兩個表格﹕
<html>
<head>
<META http-equiv="Content-Type" content="text/html; charset=gb2312">
<META http-equiv="Content-Style-Type" content="text/css">
<title>百分比表格</title>
</head>
<body>
<table width="200" border="1">
<tr height="80">
<td width="50">1234567890123456789012345678901234567890123456789012345678901234567890</td>
<td width="50"></td>
<td width="50"></td>
<td width="50"></td>
</tr>
</table>
</body>
</html>


<html>
<head>
<META http-equiv="Content-Type" content="text/html; charset=gb2312">
<META http-equiv="Content-Style-Type" content="text/css">
<title>象素表格</title>
</head>
<body>
<table width="80%" border="1">
<tr height="20">
<td width="30%"></td>
<td width="30%">3</td>
<td width="30%">3</td>
<td width="10%">3</td>
</tr>
</table>
</body>
</html>
為什么數據過長他不會自動換行﹗

注﹕ 好象于編輯器有點關系﹐DW Notepad UltraEdit編輯都不會自動換行﹐frontpage編輯的有時候會換行﹗
關于﹕noWrap 我也試過﹐這個到是可以使能換行的不換行﹗