function toggleVisibility(e)
{
	var func='none';
	if( $('semaphore' ) )
	{
		sAdvice='';
		sCurrent='';
		lVisible=$('semaphore').visible();
		if( lVisible )
		{
			func='hide';
			sCurrent='an outline';
			sAdvice='the complete titles and abstracts';
		}
		else
		{
			func='show';
			sCurrent='complete titles and abstracts';
			sAdvice='a simpler outline';
		}
		$$('.talkabstract').invoke(func);
		$('currentagenda').update( sCurrent );
		$('newagenda').update( sAdvice );	
	}
	e.stop();
}

document.observe( 'dom:loaded', function() {
	$('newagenda').observe( 'click', toggleVisibility );
});