diff --git a/documentation/extensions/hoxt.md b/documentation/extensions/hoxt.md
index 55bb17f3a..a1d79066a 100644
--- a/documentation/extensions/hoxt.md
+++ b/documentation/extensions/hoxt.md
@@ -73,11 +73,11 @@ HttpOverXmppReq req = new HttpOverXmppReq(HttpMethod.POST, "/mailbox");
 req.setVersion("1.1");
 
 // prepare headers
-Set<Header> set = new HashSet<Header>();
-set.add(new Header("Host", "juliet.capulet.com"));
-set.add(new Header("Content-Type", "application/x-www-form- urlencoded"));
-set.add(new Header("Content-Length", Integer.toString(urlEncodedMessage.length())));
-req.setHeaders(new HeadersExtension(set));
+List<Header> list = new ArrayList<Header>();
+list.add(new Header("Host", "juliet.capulet.com"));
+list.add(new Header("Content-Type", "application/x-www-form- urlencoded"));
+list.add(new Header("Content-Length", Integer.toString(urlEncodedMessage.length())));
+req.setHeaders(new HeadersExtension(list));
 
 // provide body or request (not mandatory, - empty body is used for GET)
 AbstractHttpOverXmpp.Text child = new AbstractHttpOverXmpp.Text(urlEncodedMessage);