diff --git a/keyserver/src/responders/message-responders.js b/keyserver/src/responders/message-responders.js
index b1daa65e1..de36efab5 100644
--- a/keyserver/src/responders/message-responders.js
+++ b/keyserver/src/responders/message-responders.js
@@ -1,169 +1,217 @@
 // @flow
 
 import invariant from 'invariant';
 import t from 'tcomb';
 
 import { createMediaMessageData, trimMessage } from 'lib/shared/message-utils';
 import {
   messageTypes,
   type SendTextMessageRequest,
   type SendMultimediaMessageRequest,
   type FetchMessageInfosResponse,
   type FetchMessageInfosRequest,
   defaultNumberPerThread,
   type SendMessageResponse,
 } from 'lib/types/message-types';
 import type { TextMessageData } from 'lib/types/messages/text';
 import { threadPermissions } from 'lib/types/thread-types';
 import { ServerError } from 'lib/utils/errors';
 import { tShape, tMediaMessageMedia } from 'lib/utils/validation-utils';
 
 import createMessages from '../creators/message-creator';
 import {
   fetchMessageInfos,
   fetchMessageInfoForLocalID,
 } from '../fetchers/message-fetchers';
 import { checkThreadPermission } from '../fetchers/thread-permission-fetchers';
-import { fetchMedia } from '../fetchers/upload-fetchers';
+import {
+  fetchMedia,
+  fetchMediaFromMediaMessageContent,
+} from '../fetchers/upload-fetchers';
 import type { Viewer } from '../session/viewer';
-import { assignMedia } from '../updaters/upload-updaters';
+import {
+  assignMedia,
+  assignMessageContainerToMedia,
+} from '../updaters/upload-updaters';
 import { validateInput } from '../utils/validation-utils';
 
 const sendTextMessageRequestInputValidator = tShape({
   threadID: t.String,
   localID: t.maybe(t.String),
   text: t.String,
 });
 async function textMessageCreationResponder(
   viewer: Viewer,
   input: any,
 ): Promise<SendMessageResponse> {
   const request: SendTextMessageRequest = input;
   await validateInput(viewer, sendTextMessageRequestInputValidator, request);
 
   const { threadID, localID, text: rawText } = request;
   const text = trimMessage(rawText);
   if (!text) {
     throw new ServerError('invalid_parameters');
   }
 
   const hasPermission = await checkThreadPermission(
     viewer,
     threadID,
     threadPermissions.VOICED,
   );
   if (!hasPermission) {
     throw new ServerError('invalid_parameters');
   }
 
   const messageData: TextMessageData = {
     type: messageTypes.TEXT,
     threadID,
     creatorID: viewer.id,
     time: Date.now(),
     text,
   };
   if (localID) {
     messageData.localID = localID;
   }
   const rawMessageInfos = await createMessages(viewer, [messageData]);
 
   return { newMessageInfo: rawMessageInfos[0] };
 }
 
 const fetchMessageInfosRequestInputValidator = tShape({
   cursors: t.dict(t.String, t.maybe(t.String)),
   numberPerThread: t.maybe(t.Number),
 });
 async function messageFetchResponder(
   viewer: Viewer,
   input: any,
 ): Promise<FetchMessageInfosResponse> {
   const request: FetchMessageInfosRequest = input;
   await validateInput(viewer, fetchMessageInfosRequestInputValidator, request);
   const response = await fetchMessageInfos(
     viewer,
     { threadCursors: request.cursors },
     request.numberPerThread ? request.numberPerThread : defaultNumberPerThread,
   );
   return { ...response, userInfos: {} };
 }
 
 const sendMultimediaMessageRequestInputValidator = t.union([
   tShape({
     threadID: t.String,
     localID: t.String,
     mediaIDs: t.list(t.String),
   }),
   tShape({
     threadID: t.String,
     localID: t.String,
     mediaMessageContents: t.list(tMediaMessageMedia),
   }),
 ]);
 async function multimediaMessageCreationResponder(
   viewer: Viewer,
   input: any,
 ): Promise<SendMessageResponse> {
   const request: SendMultimediaMessageRequest = input;
   await validateInput(
     viewer,
     sendMultimediaMessageRequestInputValidator,
     request,
   );
-  return legacyMultimediaMessageCreationResponder(viewer, request);
+
+  if (request.mediaIDs) {
+    return legacyMultimediaMessageCreationResponder(viewer, request);
+  }
+
+  const { threadID, localID, mediaMessageContents } = request;
+  if (mediaMessageContents.length === 0) {
+    throw new ServerError('invalid_parameters');
+  }
+
+  const hasPermission = await checkThreadPermission(
+    viewer,
+    threadID,
+    threadPermissions.VOICED,
+  );
+  if (!hasPermission) {
+    throw new ServerError('invalid_parameters');
+  }
+
+  const [media, existingMessageInfo] = await Promise.all([
+    fetchMediaFromMediaMessageContent(viewer, mediaMessageContents),
+    fetchMessageInfoForLocalID(viewer, localID),
+  ]);
+
+  if (media.length !== mediaMessageContents.length && !existingMessageInfo) {
+    throw new ServerError('invalid_parameters');
+  }
+
+  const messageData = createMediaMessageData({
+    localID,
+    threadID,
+    creatorID: viewer.id,
+    media,
+  });
+  const [newMessageInfo] = await createMessages(viewer, [messageData]);
+  const { id } = newMessageInfo;
+  invariant(
+    id !== null && id !== undefined,
+    'serverID should be set in createMessages result',
+  );
+
+  await assignMessageContainerToMedia(viewer, mediaMessageContents, id);
+  return { newMessageInfo };
 }
 
 async function legacyMultimediaMessageCreationResponder(
   viewer: Viewer,
   request: SendMultimediaMessageRequest,
 ): Promise<SendMessageResponse> {
   const { threadID, localID } = request;
   const mediaIDs = request.mediaIDs
     ? request.mediaIDs
     : request.mediaMessageContents.map(contents => contents.uploadID);
 
   if (mediaIDs.length === 0) {
     throw new ServerError('invalid_parameters');
   }
 
   const hasPermission = await checkThreadPermission(
     viewer,
     threadID,
     threadPermissions.VOICED,
   );
   if (!hasPermission) {
     throw new ServerError('invalid_parameters');
   }
 
   const [media, existingMessageInfo] = await Promise.all([
     fetchMedia(viewer, mediaIDs),
     fetchMessageInfoForLocalID(viewer, localID),
   ]);
   if (media.length !== mediaIDs.length && !existingMessageInfo) {
     throw new ServerError('invalid_parameters');
   }
 
   const messageData = createMediaMessageData({
     localID,
     threadID,
     creatorID: viewer.id,
     media,
   });
   const [newMessageInfo] = await createMessages(viewer, [messageData]);
 
   const { id } = newMessageInfo;
   invariant(
     id !== null && id !== undefined,
     'serverID should be set in createMessages result',
   );
   await assignMedia(viewer, mediaIDs, id);
 
   return { newMessageInfo };
 }
 
 export {
   textMessageCreationResponder,
   messageFetchResponder,
   multimediaMessageCreationResponder,
 };