diff --git a/appengine/mailjet/src/main/java/com/example/appengine/mailjet/MailjetServlet.java b/appengine/mailjet/src/main/java/com/example/appengine/mailjet/MailjetServlet.java
index e9922a71438..2b13d055f72 100644
--- a/appengine/mailjet/src/main/java/com/example/appengine/mailjet/MailjetServlet.java
+++ b/appengine/mailjet/src/main/java/com/example/appengine/mailjet/MailjetServlet.java
@@ -20,8 +20,9 @@
 import com.mailjet.client.MailjetRequest;
 import com.mailjet.client.MailjetResponse;
 import com.mailjet.client.errors.MailjetException;
+import com.mailjet.client.ClientOptions;
 import com.mailjet.client.errors.MailjetSocketTimeoutException;
-import com.mailjet.client.resource.Email;
+import com.mailjet.client.resource.Emailv31;
 // [END mailjet_imports]
 
 import org.json.JSONArray;
@@ -39,7 +40,7 @@
 public class MailjetServlet extends HttpServlet {
   private static final String MAILJET_API_KEY = System.getenv("MAILJET_API_KEY");
   private static final String MAILJET_SECRET_KEY = System.getenv("MAILJET_SECRET_KEY");
-  private MailjetClient client = new MailjetClient(MAILJET_API_KEY, MAILJET_SECRET_KEY);
+  private MailjetClient client = new MailjetClient(MAILJET_API_KEY, MAILJET_SECRET_KEY, new ClientOptions("v3.1"));
 
   @Override
   public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException,
@@ -47,15 +48,18 @@ public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOEx
     String recipient = req.getParameter("to");
     String sender = req.getParameter("from");
 
-    MailjetRequest email = new MailjetRequest(Email.resource)
-        .property(Email.FROMEMAIL, sender)
-        .property(Email.FROMNAME, "pandora")
-        .property(Email.SUBJECT, "Your email flight plan!")
-        .property(Email.TEXTPART,
-            "Dear passenger, welcome to Mailjet! May the delivery force be with you!")
-        .property(Email.HTMLPART,
-            "<h3>Dear passenger, welcome to Mailjet!</h3><br/>May the delivery force be with you!")
-        .property(Email.RECIPIENTS, new JSONArray().put(new JSONObject().put("Email", recipient)));
+    MailjetRequest email = new MailjetRequest(Emailv31.resource)
+      .property(Emailv31.MESSAGES, new JSONArray()
+        .put(new JSONObject()
+          .put(Emailv31.Message.FROM, new JSONObject()
+            .put("Email", sender)
+            .put("Name", "pandora"))
+          .put(Emailv31.Message.TO, new JSONArray()
+            .put(new JSONObject()
+              .put("Email", recipient)))
+          .put(Emailv31.Message.SUBJECT, "Your email flight plan!")
+          .put(Emailv31.Message.TEXTPART, "Dear passenger, welcome to Mailjet! May the delivery force be with you!")
+          .put(Emailv31.Message.HTMLPART, "<h3>Dear passenger, welcome to Mailjet!</h3><br />May the delivery force be with you!")));
 
     try {
       // trigger the API call
diff --git a/compute/mailjet/src/main/java/com/example/compute/mailjet/MailjetSender.java b/compute/mailjet/src/main/java/com/example/compute/mailjet/MailjetSender.java
index 5d469c8bc43..2492f8baad8 100644
--- a/compute/mailjet/src/main/java/com/example/compute/mailjet/MailjetSender.java
+++ b/compute/mailjet/src/main/java/com/example/compute/mailjet/MailjetSender.java
@@ -21,8 +21,9 @@
 import com.mailjet.client.MailjetRequest;
 import com.mailjet.client.MailjetResponse;
 import com.mailjet.client.errors.MailjetException;
+import com.mailjet.client.ClientOptions;
 import com.mailjet.client.errors.MailjetSocketTimeoutException;
-import com.mailjet.client.resource.Email;
+import com.mailjet.client.resource.Emailv31;
 // [END mailjet_imports]
 
 import org.json.JSONArray;
@@ -34,7 +35,7 @@ public class MailjetSender{
   public static void main(String[] args) throws MailjetException, MailjetSocketTimeoutException {
     final String mailjetApiKey = "YOUR-MAILJET-API-KEY";
     final String mailjetSecretKey = "YOUR-MAILJET-SECRET-KEY";
-    MailjetClient client = new MailjetClient(mailjetApiKey, mailjetSecretKey);
+    MailjetClient client = new MailjetClient(mailjetApiKey, mailjetSecretKey, new ClientOptions("v3.1"));
 
     MailjetSender sender = new MailjetSender();
     sender.sendMailjet(args[0], args[1], client);
@@ -42,15 +43,19 @@ public static void main(String[] args) throws MailjetException, MailjetSocketTim
 
   public MailjetResponse sendMailjet(String recipient, String sender, MailjetClient client)
   throws MailjetException, MailjetSocketTimeoutException {
-    MailjetRequest email = new MailjetRequest(Email.resource)
-        .property(Email.FROMEMAIL, sender)
-        .property(Email.FROMNAME, "pandora")
-        .property(Email.SUBJECT, "Your email flight plan!")
-        .property(Email.TEXTPART,
-            "Dear passenger, welcome to Mailjet! May the delivery force be with you!")
-        .property(Email.HTMLPART,
-            "<h3>Dear passenger, welcome to Mailjet!</h3><br/>May the delivery force be with you!")
-        .property(Email.RECIPIENTS, new JSONArray().put(new JSONObject().put("Email", recipient)));
+    MailjetRequest email = new MailjetRequest(Emailv31.resource)
+      .property(Emailv31.MESSAGES, new JSONArray()
+        .put(new JSONObject()
+          .put(Emailv31.Message.FROM, new JSONObject()
+            .put("Email", sender)
+            .put("Name", "pandora"))
+          .put(Emailv31.Message.TO, new JSONArray()
+            .put(new JSONObject()
+              .put("Email", recipient)))
+          .put(Emailv31.Message.SUBJECT, "Your email flight plan!")
+          .put(Emailv31.Message.TEXTPART, "Dear passenger, welcome to Mailjet! May the delivery force be with you!")
+          .put(Emailv31.Message.HTMLPART, "<h3>Dear passenger, welcome to Mailjet!</h3><br />May the delivery force be with you!")));
+
 
     try {
       // trigger the API call
diff --git a/flexible/mailjet/src/main/java/com/example/mailjet/MailjetServlet.java b/flexible/mailjet/src/main/java/com/example/mailjet/MailjetServlet.java
index 72efc229545..021b49964da 100644
--- a/flexible/mailjet/src/main/java/com/example/mailjet/MailjetServlet.java
+++ b/flexible/mailjet/src/main/java/com/example/mailjet/MailjetServlet.java
@@ -22,7 +22,8 @@
 import com.mailjet.client.MailjetResponse;
 import com.mailjet.client.errors.MailjetException;
 import com.mailjet.client.errors.MailjetSocketTimeoutException;
-import com.mailjet.client.resource.Email;
+import com.mailjet.client.ClientOptions;
+import com.mailjet.client.resource.Emailv31;
 // [END mailjet_imports]
 
 import org.json.JSONArray;
@@ -42,7 +43,7 @@
 public class MailjetServlet extends HttpServlet {
   private static final String MAILJET_API_KEY = System.getenv("MAILJET_API_KEY");
   private static final String MAILJET_SECRET_KEY = System.getenv("MAILJET_SECRET_KEY");
-  private MailjetClient client = new MailjetClient(MAILJET_API_KEY, MAILJET_SECRET_KEY);
+  private MailjetClient client = new MailjetClient(MAILJET_API_KEY, MAILJET_SECRET_KEY, new ClientOptions("v3.1"));
 
   @Override
   public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException,
@@ -50,15 +51,18 @@ public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOEx
     String recipient = req.getParameter("to");
     String sender = req.getParameter("from");
 
-    MailjetRequest email = new MailjetRequest(Email.resource)
-        .property(Email.FROMEMAIL, sender)
-        .property(Email.FROMNAME, "pandora")
-        .property(Email.SUBJECT, "Your email flight plan!")
-        .property(Email.TEXTPART,
-            "Dear passenger, welcome to Mailjet! May the delivery force be with you!")
-        .property(Email.HTMLPART,
-            "<h3>Dear passenger, welcome to Mailjet!</h3><br/>May the delivery force be with you!")
-        .property(Email.RECIPIENTS, new JSONArray().put(new JSONObject().put("Email", recipient)));
+    MailjetRequest email = new MailjetRequest(Emailv31.resource)
+      .property(Emailv31.MESSAGES, new JSONArray()
+        .put(new JSONObject()
+          .put(Emailv31.Message.FROM, new JSONObject()
+            .put("Email", sender)
+            .put("Name", "Mailjet Pilot"))
+          .put(Emailv31.Message.TO, new JSONArray()
+            .put(new JSONObject()
+              .put("Email", recipient)))
+          .put(Emailv31.Message.SUBJECT, "Your email flight plan!")
+          .put(Emailv31.Message.TEXTPART, "Dear passenger, welcome to Mailjet! May the delivery force be with you!")
+          .put(Emailv31.Message.HTMLPART, "<h3>Dear passenger, welcome to Mailjet!</h3><br />May the delivery force be with you!")));
 
     try {
       // trigger the API call