diff --git a/test/http_binding_0_1.js b/test/http_binding_0_1.js
index d5188d3..864bbaa 100644
--- a/test/http_binding_0_1.js
+++ b/test/http_binding_0_1.js
@@ -15,17 +15,24 @@ const data = {
   foo: "bar"
 };
 
+const ext1Name  = "extension1";
+const ext1Value = "foobar";
+const ext2Name  = "extension2";
+const ext2Value = "acme";
+
 const Structured01 = Cloudevent.bindings["http-structured0.1"];
 const Binary01     = Cloudevent.bindings["http-binary0.1"];
 
-var cloudevent = 
+var cloudevent =
   new Cloudevent()
     .type(type)
     .source(source)
     .contenttype(ceContentType)
     .time(now)
     .schemaurl(schemaurl)
-    .data(data);
+    .data(data)
+    .addExtension(ext1Name, ext1Value)
+    .addExtension(ext2Name, ext2Value);
 
 cloudevent.eventTypeVersion("1.0.0");
 
@@ -90,6 +97,7 @@ describe("HTTP Transport Binding - Version 0.1", () => {
               .to.have.property("CE-EventType");
           });
       });
+
       it("HTTP Header contains 'CE-EventTypeVersion'", () => {
         return httpbinary01.emit(cloudevent)
           .then((response) => {
@@ -97,6 +105,7 @@ describe("HTTP Transport Binding - Version 0.1", () => {
               .to.have.property("CE-EventTypeVersion");
           });
       });
+
       it("HTTP Header contains 'CE-CloudEventsVersion'", () => {
         return httpbinary01.emit(cloudevent)
           .then((response) => {
@@ -104,6 +113,7 @@ describe("HTTP Transport Binding - Version 0.1", () => {
               .to.have.property("CE-CloudEventsVersion");
           });
       });
+
       it("HTTP Header contains 'CE-Source'", () => {
         return httpbinary01.emit(cloudevent)
           .then((response) => {
@@ -111,6 +121,7 @@ describe("HTTP Transport Binding - Version 0.1", () => {
               .to.have.property("CE-Source");
           });
       });
+
       it("HTTP Header contains 'CE-EventID'", () => {
         return httpbinary01.emit(cloudevent)
           .then((response) => {
@@ -118,6 +129,7 @@ describe("HTTP Transport Binding - Version 0.1", () => {
               .to.have.property("CE-EventID");
           });
       });
+
       it("HTTP Header contains 'CE-EventTime'", () => {
         return httpbinary01.emit(cloudevent)
           .then((response) => {
@@ -125,6 +137,7 @@ describe("HTTP Transport Binding - Version 0.1", () => {
               .to.have.property("CE-EventTime");
           });
       });
+
       it("HTTP Header contains 'CE-SchemaURL'", () => {
         return httpbinary01.emit(cloudevent)
           .then((response) => {
@@ -132,6 +145,14 @@ describe("HTTP Transport Binding - Version 0.1", () => {
               .to.have.property("CE-SchemaURL");
           });
       });
+
+      it("HTTP Header contains 'CE-X-Extension1' as extension", () => {
+        return httpbinary01.emit(cloudevent)
+          .then((response) => {
+            expect(response.config.headers)
+              .to.have.property("CE-X-Extension1");
+          });
+      });
     });
   });
 });