diff --git a/lib/neography/rest.rb b/lib/neography/rest.rb
index 219ec1e..2b1d414 100644
--- a/lib/neography/rest.rb
+++ b/lib/neography/rest.rb
@@ -437,8 +437,8 @@ def execute_script(script, params = {})
 
     # unmanaged extensions
 
-    def post_extension(path, params = {})
-      @extensions.post(path, params)
+    def post_extension(path, params = {}, headers = nil)
+      @extensions.post(path, params, headers)
     end
 
     def get_extension(path)
diff --git a/lib/neography/rest/extensions.rb b/lib/neography/rest/extensions.rb
index ff02e65..4bed2bd 100644
--- a/lib/neography/rest/extensions.rb
+++ b/lib/neography/rest/extensions.rb
@@ -11,10 +11,10 @@ def get(path)
         @connection.get(path)
       end
 
-      def post(path, body = {})
+      def post(path, body = {}, headers = nil)
         options = {
           :body => body.to_json,
-          :headers => json_content_type.merge({'Accept' => 'application/json;stream=true'})
+          :headers => headers || json_content_type.merge({'Accept' => 'application/json;stream=true'})
         }
 
         @connection.post(path, options)