Background colour of SPAN tags.

I give up on this...
None of these javascript lines will set the background colour.
Any ideas ?

This needs to work in both IE and Netscape, including NS6 if possible.

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<span name="testt" > This should have a nasty red background </span>
<br>

<script>


//function to set span background color
function setcol() {
     //document.testt.style.background='#ff0033';     //NO
     //testt.style.background='#ff0033';          //NO          
     //testt.background='#ff0033';               //NO
     //document.testt.style.backgroundcolor='#ff0033';     //NO
     //testt.style.backgroundcolor='#ff0033';          //NO
     testt.backgroundcolor='#ff0033';               //NO
}

setcol();
</script>


<br>
<span name="testt2" style="background:#ff0033" > Like this </span>

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Thanks, quick, clear response will earn an A grade.