diff --git a/ethcore/src/builtin.rs b/ethcore/src/builtin.rs
index d5dc459b2..7f71802b3 100644
--- a/ethcore/src/builtin.rs
+++ b/ethcore/src/builtin.rs
@@ -352,7 +352,7 @@ fn read_point(reader: &mut io::Chain<&[u8], io::Repeat>) -> Result<::bn::G1, Err
 	let px = Fq::from_slice(&buf[0..32]).map_err(|_| Error::from("Invalid point x coordinate"))?;
 
 	reader.read_exact(&mut buf[..]).expect("reading from zero-extended memory cannot fail; qed");
-	let py = Fq::from_slice(&buf[0..32]).map_err(|_| Error::from("Invalid point x coordinate"))?;
+	let py = Fq::from_slice(&buf[0..32]).map_err(|_| Error::from("Invalid point y coordinate"))?;
 
 	Ok(
 		if px == Fq::zero() && py == Fq::zero() {