diff --git a/Cargo.lock b/Cargo.lock
index 7c1bdbfaf..509e60aa4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -538,7 +538,7 @@ dependencies = [
 [[package]]
 name = "jsonrpc-http-server"
 version = "5.0.1"
-source = "git+https://github.com/debris/jsonrpc-http-server.git#239066b94660a1af24c8b2efc16e800f9c7cce18"
+source = "git+https://github.com/debris/jsonrpc-http-server.git#e728f2e080799b7a62b0b5cf5fa9d4ad65cd8c96"
 dependencies = [
  "hyper 0.9.0-mio (git+https://github.com/hyperium/hyper?branch=mio)",
  "jsonrpc-core 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/parity/main.rs b/parity/main.rs
index bbf7e27a9..94466e0e2 100644
--- a/parity/main.rs
+++ b/parity/main.rs
@@ -133,8 +133,7 @@ API and Console Options:
   --jsonrpc-interface IP   Specify the hostname portion of the JSONRPC API
                            server, IP should be an interface's IP address, or
                            all (all interfaces) or local [default: local].
-  --jsonrpc-cors URL       Specify CORS header for JSON-RPC API responses
-                           [default: null].
+  --jsonrpc-cors URL       Specify CORS header for JSON-RPC API responses.
   --jsonrpc-apis APIS      Specify the APIs available through the JSONRPC
                            interface. APIS is a comma-delimited list of API
                            name. Possible name are web3, eth and net.
@@ -242,7 +241,7 @@ struct Args {
 	flag_jsonrpc: bool,
 	flag_jsonrpc_interface: String,
 	flag_jsonrpc_port: u16,
-	flag_jsonrpc_cors: String,
+	flag_jsonrpc_cors: Option<String>,
 	flag_jsonrpc_apis: String,
 	flag_webapp: bool,
 	flag_webapp_port: u16,
@@ -307,7 +306,7 @@ fn setup_rpc_server(
 	secret_store: Arc<AccountService>,
 	miner: Arc<Miner>,
 	url: &SocketAddr,
-	cors_domain: &str,
+	cors_domain: Option<String>,
 	apis: Vec<&str>,
 ) -> RpcServer {
 	use rpc::v1::*;
@@ -380,7 +379,7 @@ fn setup_rpc_server(
 	_secret_store: Arc<AccountService>,
 	_miner: Arc<Miner>,
 	_url: &str,
-	_cors_domain: &str,
+	_cors_domain: Option<String>,
 	_apis: Vec<&str>,
 ) -> ! {
 	die!("Your Parity version has been compiled without JSON-RPC support.")
@@ -713,7 +712,7 @@ impl Configuration {
 				self.args.flag_rpcport.unwrap_or(self.args.flag_jsonrpc_port)
 			);
 			let addr = SocketAddr::from_str(&url).unwrap_or_else(|_| die!("{}: Invalid JSONRPC listen host/port given.", url));
-			let cors_domain = self.args.flag_rpccorsdomain.as_ref().unwrap_or(&self.args.flag_jsonrpc_cors);
+			let cors_domain = self.args.flag_jsonrpc_cors.clone().or(self.args.flag_rpccorsdomain.clone());
 
 			Some(setup_rpc_server(
 				service.client(),
@@ -721,7 +720,7 @@ impl Configuration {
 				account_service.clone(),
 				miner.clone(),
 				&addr,
-				&cors_domain,
+				cors_domain,
 				apis.split(',').collect()
 			))
 		} else {
diff --git a/rpc/src/lib.rs b/rpc/src/lib.rs
index f059750d2..f79cbe828 100644
--- a/rpc/src/lib.rs
+++ b/rpc/src/lib.rs
@@ -58,8 +58,8 @@ impl RpcServer {
 	}
 
 	/// Start server asynchronously and returns result with `Server` handle on success or an error.
-	pub fn start_http(&self, addr: &SocketAddr, cors_domain: &str) -> Result<Server, RpcServerError> {
+	pub fn start_http(&self, addr: &SocketAddr, cors_domain: Option<String>) -> Result<Server, RpcServerError> {
 		let cors_domain = cors_domain.to_owned();
-		Server::start(addr, self.handler.clone(), jsonrpc_http_server::AccessControlAllowOrigin::Value(cors_domain))
+		Server::start(addr, self.handler.clone(), cors_domain.map(jsonrpc_http_server::AccessControlAllowOrigin::Value))
 	}
 }