diff --git a/ethbloom/Cargo.toml b/ethbloom/Cargo.toml
index 5df4aac..81c49b7 100644
--- a/ethbloom/Cargo.toml
+++ b/ethbloom/Cargo.toml
@@ -17,7 +17,7 @@ serde = { version = "1.0", optional = true }
 
 [dev-dependencies]
 rand = { version = "0.4" }
-rustc-hex = "2.0"
+rustc-hex = "1.0.0"
 
 [features]
 default = ["std", "heapsizeof", "serialize", "fixed-hash/libc"]