function getElementsByClassName( className ){
	var children = document.getElementsByTagName( '*' ) || document.all;
	var elements = new Array();
	
	for( var i = 0; i < children.length; i++ ){
		var child = children[ i ];
		var classNames = child.className.split( ' ' );
		for( var j = 0; j < classNames.length; j++ ){
			if ( classNames[ j ] == className ){
				elements.push( child );
				break;
			}
		}
	}
	return elements;
}

function showInfo( pageId ){
	allPages = getElementsByClassName( 'map_info_content' );
	for( var i = 0; i < allPages.length; i++ ){
		allPages[ i ].style.display = 'none';
	}
	chosenPage = document.getElementById( pageId );
	chosenPage.style.display = '';
}