                 let deliveredHeaders = castedJSON!["headers"] as? [String : AnyObject]
                 XCTAssert(deliveredHeaders != nil)
                 
-                RequestTests.assertRequestParametersNotEqual(deliveredHeaders!, toOriginalParameters: options.headers!)
+                RequestTests.assertRequestParametersNotEqual(deliveredHeaders!, toOriginalParameters: headers)
         }
         
         waitForExpectationsWithTimeout(2, handler: nil)

        let successExpectation = expectationWithDescription("Received status 200")
        let handler = responseHandler(expectation: successExpectation)
        let service = WebService(baseURLString: baseURL)
        var options = WebService.EndpointOptions()
        options.headers = ["Some-Test-Header" :"testValue"]
        
        let task = service
            .GET("/get", parameters: nil, options: options)
            .response { data, response in
                
                let httpResponse = response as! NSHTTPURLResponse

        let handler = responseHandler(expectation: successExpectation)
        let service = WebService(baseURLString: baseURL)
        let parameters = ["foo" : "bar", "number" : 42]
        
        let task = service
            .POST("/post",
                parameters: parameters,
                options: [.ParameterEncoding(.JSON)])
            .response { data, response in
                
                let httpResponse = response as! NSHTTPURLResponse
