function start_pipe(mode)
{
	// Construct new url 'newu' [pe_loc]/pe.htm?pe_cfg=[dlh]/pe_cfg.htm

	// pe_loc is defined in index?.htm and is guaranteed to have a trailing slash
	newu = pe_loc + "protexpl/pe.htm?nco=1&pm=" + mode + "&";
	one_word_presentation_name = one_word_presentation_name.replace(/ /g, "_");
	newu += "ssn=" + one_word_presentation_name + "&"; // Short Session Name

	var dlh = unescape(document.location.href);
	var iq = dlh.indexOf("?");
	if (iq != -1)
		dlh	= dlh.substring(0, iq);

	var is = dlh.lastIndexOf("/");
	if (is == -1)
		alert("ERROR: Unanticipated absence of slash in url\n" +
			dlh);
	else
	{
		dlh = dlh.substring(0, is + 1);
		dlh = escape(dlh); //fails to work!?
		newu += "pe_cfg=" + dlh + "pe_cfg.htm&";

		top.pipemode_selected = true;

//		if (confirm(newu))
			top.pipetop.document.location.href = newu;
	}
}