diff --git a/Cargo.lock b/Cargo.lock
index 0caea9b8e..6285f159b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -880,18 +880,6 @@ name = "itoa"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "jsonrpc-core"
-version = "3.0.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "parking_lot 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 0.8.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_codegen 0.8.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "jsonrpc-core"
 version = "4.0.0"
@@ -1332,7 +1320,7 @@ dependencies = [
  "ethcore-signer 1.5.0",
  "ethcore-util 1.5.0",
  "futures 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "jsonrpc-core 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "jsonrpc-core 4.0.0 (git+https://github.com/ethcore/jsonrpc.git)",
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1368,17 +1356,6 @@ dependencies = [
  "parity-dapps-glue 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "parking_lot"
-version = "0.2.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "smallvec 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "parking_lot"
 version = "0.3.6"
@@ -2182,7 +2159,6 @@ dependencies = [
 "checksum isatty 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7408a548dc0e406b7912d9f84c261cc533c1866e047644a811c133c56041ac0c"
 "checksum itertools 0.4.13 (registry+https://github.com/rust-lang/crates.io-index)" = "086e1fa5fe48840b1cfdef3a20c7e3115599f8d5c4c87ef32a794a7cdd184d76"
 "checksum itoa 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ae3088ea4baeceb0284ee9eea42f591226e6beaecf65373e41b38d95a1b8e7a1"
-"checksum jsonrpc-core 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "3c5094610b07f28f3edaf3947b732dadb31dbba4941d4d0c1c7a8350208f4414"
 "checksum jsonrpc-core 4.0.0 (git+https://github.com/ethcore/jsonrpc.git)" = "<none>"
 "checksum jsonrpc-http-server 6.1.1 (git+https://github.com/ethcore/jsonrpc.git)" = "<none>"
 "checksum jsonrpc-ipc-server 0.2.4 (git+https://github.com/ethcore/jsonrpc.git)" = "<none>"
@@ -2230,7 +2206,6 @@ dependencies = [
 "checksum owning_ref 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "8d91377085359426407a287ab16884a0111ba473aa6844ff01d4ec20ce3d75e7"
 "checksum parity-dapps-glue 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "98378dec0a185da2b7180308752f0bad73aaa949c3e0a3b0528d0e067945f7ab"
 "checksum parity-ui-precompiled 1.4.0 (git+https://github.com/ethcore/js-precompiled.git)" = "<none>"
-"checksum parking_lot 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "968f685642555d2f7e202c48b8b11de80569e9bfea817f7f12d7c61aac62d4e6"
 "checksum parking_lot 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "e1435e7a2a00dfebededd6c6bdbd54008001e94b4a2aadd6aef0dc4c56317621"
 "checksum parking_lot_core 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fb1b97670a2ffadce7c397fb80a3d687c4f3060140b885621ef1653d0e5d5068"
 "checksum phf 0.7.14 (registry+https://github.com/rust-lang/crates.io-index)" = "447d9d45f2e0b4a9b532e808365abf18fc211be6ca217202fcd45236ef12f026"
diff --git a/rpc_client/Cargo.toml b/rpc_client/Cargo.toml
index 9b93a1a5b..e5c8e9b12 100644
--- a/rpc_client/Cargo.toml
+++ b/rpc_client/Cargo.toml
@@ -8,7 +8,6 @@ version = "1.4.0"
 
 [dependencies]
 futures = "0.1"
-jsonrpc-core = "3.0.2"
 lazy_static = "0.2.1"
 log = "0.3.6"
 matches = "0.1.2"
@@ -17,6 +16,7 @@ serde = "0.8"
 serde_json = "0.8"
 tempdir = "0.3.5"
 url = "1.2.0"
+jsonrpc-core = { git = "https://github.com/ethcore/jsonrpc.git" }
 ws = { git = "https://github.com/ethcore/ws-rs.git", branch = "mio-upstream-stable" }
 ethcore-rpc = { path = "../rpc" }
 ethcore-signer = { path = "../signer" }
diff --git a/rpc_client/src/client.rs b/rpc_client/src/client.rs
index 9ee9f5c9d..c32b5be7a 100644
--- a/rpc_client/src/client.rs
+++ b/rpc_client/src/client.rs
@@ -36,7 +36,7 @@ use futures::{BoxFuture, Canceled, Complete, Future, oneshot, done};
 
 use jsonrpc_core::{Id, Version, Params, Error as JsonRpcError};
 use jsonrpc_core::request::MethodCall;
-use jsonrpc_core::response::{SyncOutput, Success, Failure};
+use jsonrpc_core::response::{Output, Success, Failure};
 
 /// The actual websocket connection handler, passed into the
 /// event loop of ws-rs
@@ -107,13 +107,13 @@ impl Handler for RpcHandler {
 		let ret: Result<JsonValue, JsonRpcError>;
 		let response_id;
 		let string = &msg.to_string();
-		match json::from_str::<SyncOutput>(&string) {
-			Ok(SyncOutput::Success(Success { result, id: Id::Num(id), .. })) =>
+		match json::from_str::<Output>(&string) {
+			Ok(Output::Success(Success { result, id: Id::Num(id), .. })) =>
 			{
 				ret = Ok(result);
 				response_id = id as usize;
 			}
-			Ok(SyncOutput::Failure(Failure { error, id: Id::Num(id), .. })) => {
+			Ok(Output::Failure(Failure { error, id: Id::Num(id), .. })) => {
 				ret = Err(error);
 				response_id = id as usize;
 			}