var text = "";
function gethightlightText(e)
{
    var newtext = (document.all) ? document.selection.createRange().text : document.getSelection();
    if(newtext != '')
    {
	if((text != newtext) )
        {
	    document.searchform.search.value=newtext;
	}
    }
    return true;
}

document.onmouseup = gethightlightText;
if (!document.all) document.captureEvents(Event.MOUSEUP);