diff --git a/src/ripple/rpc/impl/RPCHelpers.h b/src/ripple/rpc/impl/RPCHelpers.h
index 3dece296b..ad3cc218d 100644
--- a/src/ripple/rpc/impl/RPCHelpers.h
+++ b/src/ripple/rpc/impl/RPCHelpers.h
@@ -313,7 +313,7 @@ std::pair<PublicKey, SecretKey>
 keypairForSignature(
     Json::Value const& params,
     Json::Value& error,
-    uint apiVersion = apiVersionIfUnspecified);
+    unsigned int apiVersion = apiVersionIfUnspecified);
 
 }  // namespace RPC
 }  // namespace ripple