xhr_wr.setRequestHeader("If-Modified-Since", new Date().toUTCString());
xhr_wr.onreadystatechange = function() { return; };
if (typeof(g_debug) == 'number' && g_debug > 0
xhr_wr.setRequestHeader("If-Modified-Since", new Date().toUTCString());
xhr_wr.onreadystatechange = function() { return; };
if (typeof(g_debug) == 'number' && g_debug > 0