XPath Compiling Issues?

log.txt

valac --version
Vala 0.13.2
valac --vapidir=vapi --pkg libsoup-2.4 --pkg libxml-2.0 --thread -g --save-temps main.vala
main.vala:24.24-24.33: error: The name `type' does not exist in the context of `Xml.XPath.Object*'
		if (nodes != null && nodes.type == Xml.XPath.ObjectType.NODESET)
		                     ^^^^^^^^^^
main.vala:27.44-27.56: error: The name `nodeset' does not exist in the context of `Xml.XPath.Object*'
                                           nodes.nodeset.length());
                                           ^^^^^^^^^^^^^
Compilation failed: 4 error(s), 0 warning(s)
main.vala:28.24-28.36: error: The name `nodeset' does not exist in the context of `Xml.XPath.Object*'
			for (int i = 0; i < nodes.nodeset.length(); i++) {
			                    ^^^^^^^^^^^^^
main.vala:30.35-30.47: error: The name `nodeset' does not exist in the context of `Xml.XPath.Object*'
                                  nodes.nodeset.item(i).get_path());
                                  ^^^^^^^^^^^^^

main.vala

void main () {
	var id = "105113917365398481197";
	var url = @"https://www.googleapis.com/buzz/v1/activities/$id/@public";
	
	// create an HTTP session to google
	var session = new Soup.SessionAsync ();
	var message = new Soup.Message ("GET", url);

	// send the HTTP request
	session.queue_message (message, (sess, mess) => {
		// Load XML
		var doc = Xml.Parser.parse_doc ((string) mess.response_body.data);
		
		// Search for Posts
		Xml.XPath.order_doc_elements (doc);
		var xpath = new Xml.XPath.Context(doc);
		unowned Xml.XPath.Object results = xpath.eval("//content");
		
		// Go through results
		if (results != null && results.type == Xml.XPath.ObjectType.NODESET) {
			unowned Xml.XPath.NodeSet nodes = results.nodesetval;
			printerr ("got %d nodes\n", nodes.length());
			for (int i = 0; i < nodes.length(); i++) {
				unowned Xml.Node node = nodes.item(i);
				printerr ("  -> %s\n", node.get_path());
			}
		}
	});
	session.send_message (message);
}

Makefile

all:
	valac --version
	valac --vapidir=vapi --pkg libsoup-2.4 --pkg libxml-2.0 --thread -g --save-temps main.vala
	./main