Greetings.

I've inherited a site that is pretty bad shape. I managed to fix most of the errors, but I have this 1 that I haven't been able to find a legal replacement for. It basically makes a top horizontal line using a gif ( 50px x 50px ) background the full width of the screen:
Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">


<html xmlns="http://www.w3.org/1999/xhtml">


 <head>
  <title>Cause it needs 1</title>
  <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"/>
  <meta http-equiv="Content-Style-Type" content="text/css"/>
 </head>


 <body style="MARGIN:0px" text="#000000">


 <table width="100%">
  <tbody>
   <tr>
    <td background="images/bg.gif" colSpan="3" height="40">
    </td>
   </tr>
  </tbody>
 </table> 


<!-- W3C Validator -->  
  <p>
    <a href="http://validator.w3.org/check?uri=referer">
    <img src="http://www.w3.org/Icons/valid-xhtml10-blue.png" 
         alt="Valid XHTML 1.0 Transitional" 
         align="right"
         height="31" width="88"  border="0" />
    </a>
  </p> 
 </body>
</html>
<td> cannot have either background or colSpan

I've tried a lot of combinations of the following with no sucess:
Code:
 <style type="text/css">
#bar {
  background-image:url('bg.gif');
  background-repeat:repeat-x;  
  background-size:50px 50px;  
} 
</style>
and then
Code:
 <table width="100%">
   <tbody>
    <tr>
     <td id="bar"></td>
    </tr>
....
If anyone could shed some light on this I would deeply appriciative.

-David