diff --git a/src/sha3.rs b/src/sha3.rs
index ed3fe65a3..c251edcfb 100644
--- a/src/sha3.rs
+++ b/src/sha3.rs
@@ -1,7 +1,7 @@
 //! Wrapper around tiny-keccak crate.
 
 use std::mem::uninitialized;
-use bytes::BytesConvertable;
+use bytes::{BytesConvertable, Populatable};
 use hash::{H256, FixedHash};
 
 pub const SHA3_EMPTY: H256 = H256( [0xc5, 0xd2, 0x46, 0x01, 0x86, 0xf7, 0x23, 0x3c, 0x92, 0x7e, 0x7d, 0xb2, 0xdc, 0xc7, 0x03, 0xc0, 0xe5, 0x00, 0xb6, 0x53, 0xca, 0x82, 0x27, 0x3b, 0x7b, 0xfa, 0xd8, 0x04, 0x5d, 0x85, 0xa4, 0x70] );
@@ -23,7 +23,10 @@ extern {
 /// }
 /// ```
 pub trait Hashable {
+	/// Calculate SHA3 of this object.
 	fn sha3(&self) -> H256;
+
+	/// Calculate SHA3 of this object and place result into dest.
 	fn sha3_into(&self, dest: &mut [u8]) {
 		self.sha3().copy_to(dest);
 	}
@@ -32,9 +35,8 @@ pub trait Hashable {
 impl<T> Hashable for T where T: BytesConvertable {
 	fn sha3(&self) -> H256 {
 		unsafe {
-			let input: &[u8] = self.bytes();
 			let mut ret: H256 = uninitialized();
-			sha3_256(ret.as_mut_ptr(), ret.len(), input.as_ptr(), input.len());
+			self.sha3_into(ret.as_slice_mut());
 			ret
 		}
 	}