diff --git a/CHANGELOG.md b/CHANGELOG.md
index c6bdbb50..206bc4cd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,7 +10,9 @@ and this project adheres to
 
 - @cosmjs/tendermint-rpc: `Tendermint34Client.blockSearch` and
   `Tendermint34Client.blockSearchAll` were added to allow searching blocks in
-  Tendermint 0.34.9+ backends. This is a backport of [#815].
+  Tendermint 0.34.9+ backends. This is a backport of [#815]. Note: Decoding
+  blocks of height 1 is unsupported. This is fixed in [#815] and will be
+  released as part of CosmJS 0.26.
 
 [#815]: https://github.com/cosmos/cosmjs/pull/815
 
diff --git a/README.md b/README.md
index 20513ba4..a9886103 100644
--- a/README.md
+++ b/README.md
@@ -101,6 +101,13 @@ discussion please reach out to the team.
 
 ## Known limitations
 
+### 0.25
+
+1. Decoding blocks of height 1 is unsupported. This is fixed in [#815] and will
+   be released as part of CosmJS 0.26.
+
+[#815]: https://github.com/cosmos/cosmjs/pull/815
+
 ### 0.24
 
 1. `AuthExtension` and all higher level Stargate clients only support
diff --git a/packages/tendermint-rpc/src/tendermint34/tendermint34client.spec.ts b/packages/tendermint-rpc/src/tendermint34/tendermint34client.spec.ts
index 006b33a3..a3158348 100644
--- a/packages/tendermint-rpc/src/tendermint34/tendermint34client.spec.ts
+++ b/packages/tendermint-rpc/src/tendermint34/tendermint34client.spec.ts
@@ -234,7 +234,9 @@ function defaultTestSuite(rpcFactory: () => RpcClient, expected: ExpectedValues)
       pendingWithoutTendermint();
       const client = await Tendermint34Client.create(rpcFactory());
 
-      const query = buildQuery({ raw: "block.height >= 1 AND block.height <= 3" });
+      // Note: Block height 1 is unsupported. This is fixed in https://github.com/cosmos/cosmjs/pull/815
+      // and will be released with CosmJS 0.26.
+      const query = buildQuery({ raw: "block.height >= 2 AND block.height <= 4" });
 
       // expect one page of results
       const s1 = await client.blockSearch({ query: query, page: 1, per_page: 2 });
@@ -253,7 +255,9 @@ function defaultTestSuite(rpcFactory: () => RpcClient, expected: ExpectedValues)
       pendingWithoutTendermint();
       const client = await Tendermint34Client.create(rpcFactory());
 
-      const query = buildQuery({ raw: "block.height >= 1 AND block.height <= 3" });
+      // Note: Block height 1 is unsupported. This is fixed in https://github.com/cosmos/cosmjs/pull/815
+      // and will be released with CosmJS 0.26.
+      const query = buildQuery({ raw: "block.height >= 2 AND block.height <= 4" });
 
       const sall = await client.blockSearchAll({ query: query, per_page: 2 });
       expect(sall.totalCount).toEqual(3);