diff --git a/ethcore/src/error.rs b/ethcore/src/error.rs
index 5ba4aa0c2..cadb4fb1f 100644
--- a/ethcore/src/error.rs
+++ b/ethcore/src/error.rs
@@ -171,9 +171,9 @@ pub enum BlockError {
 	/// The same author issued different votes at the same step.
 	DoubleVote(H160),
 	/// The received block is from an incorrect proposer.
-	NotProposer(H160),
+	NotProposer(Mismatch<H160>),
 	/// Signature does not belong to an authority.
-	NotAuthority(H160)
+	NotAuthorized(H160)
 }
 
 impl fmt::Display for BlockError {
@@ -208,8 +208,8 @@ impl fmt::Display for BlockError {
 			UnknownParent(ref hash) => format!("Unknown parent: {}", hash),
 			UnknownUncleParent(ref hash) => format!("Unknown uncle parent: {}", hash),
 			DoubleVote(ref address) => format!("Author {} issued too many blocks.", address),
-			NotProposer(ref address) => format!("Author {} is not a current proposer.", address),
-			NotAuthority(ref address) => format!("Signer {} is not authorized.", address),
+			NotProposer(ref mis) => format!("Author is not a current proposer: {}", mis),
+			NotAuthorized(ref address) => format!("Signer {} is not authorized.", address),
 		};
 
 		f.write_fmt(format_args!("Block error ({})", msg))