A simple and crude method would just to be:
js code:
// txt is the xmlhttp responseText stored in a variable
txt = txt.split('<div id="1">')[1];
txt = txt.split('</div>')[0];
// txt will now be the div contents including the html
// if the content is bold for example, you will see:
// This is the <b>content</b> from the div
EDIT:
It may be possible to do this in one line:
js code:
txt = txt.split('<div id="1">')[1].split('</div>')[0];
I can't be sure of that one though without trying it, but most javascript seems to chain quite well
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