diff --git a/lib/types/messages/unsupported.js b/lib/types/messages/unsupported.js
--- a/lib/types/messages/unsupported.js
+++ b/lib/types/messages/unsupported.js
@@ -2,6 +2,10 @@
 
 import t, { type TInterface } from 'tcomb';
 
+import { rawChangeRoleMessageInfoValidator } from './change-role.js';
+import { rawEditMessageInfoValidator } from './edit.js';
+import { rawMediaMessageInfoValidator } from './media.js';
+import { rawUpdateRelationshipMessageInfoValidator } from './update-relationship.js';
 import { tID, tNumber, tShape } from '../../utils/validation-utils.js';
 import { messageTypes } from '../message-types-enum.js';
 import type { RelativeUserInfo } from '../user-types.js';
@@ -26,7 +30,18 @@
     time: t.Number,
     robotext: t.String,
     dontPrefixCreator: t.maybe(t.Boolean),
-    unsupportedMessageInfo: t.Object,
+    unsupportedMessageInfo: t.union([
+      // We include these four validators here to make sure that the keyserver
+      // does ID conversion on unsupportedMessageInfo when it's one of these
+      // types. These are the types whose message speces have shimming logic
+      // that targets codeVersions that have been released after ID conversion
+      // was introduced.
+      rawUpdateRelationshipMessageInfoValidator,
+      rawChangeRoleMessageInfoValidator,
+      rawEditMessageInfoValidator,
+      rawMediaMessageInfoValidator,
+      t.Object,
+    ]),
   });
 
 export type UnsupportedMessageInfo = {