diff --git a/src/uint256.h b/src/uint256.h
index d52604099..6c19c5868 100644
--- a/src/uint256.h
+++ b/src/uint256.h
@@ -709,7 +709,7 @@ inline const uint256 operator|(const uint256& a, const uint256& b)	  { return (b
 inline const uint256 operator+(const uint256& a, const uint256& b)	  { return (base_uint256)a +  (base_uint256)b; }
 inline const uint256 operator-(const uint256& a, const uint256& b)	  { return (base_uint256)a -  (base_uint256)b; }
 
-uint256 uint160extend256(const uint160& uSource);
+uint256 uint160extend256(const uint160& uSource, uint uNamespace);
 
 inline int Testuint256AdHoc(std::vector<std::string> vArg)
 {
diff --git a/src/utils.cpp b/src/utils.cpp
index 3ae809de7..ca6240cc2 100644
--- a/src/utils.cpp
+++ b/src/utils.cpp
@@ -1,11 +1,14 @@
 #include "utils.h"
 #include "uint256.h"
 
-uint256 uint160extend256(const uint160& uSource)
+// XXX Assume little-endian.
+uint256 uint160extend256(const uint160& uSource, uint uNamespace)
 {
 	uint256 uResult;
 
-	memcpy(uResult.begin() + (uResult.size() - uSource.size()), uSource.begin(), uSource.size());
+	// Place right justified: in most significant bits.
+	memcpy(uResult.end() - uSource.size(), uSource.begin(), uSource.size());
+	uResult.begin()[uResult.size() - uSource.size() - 1]	= uNamespace;
 
 	return uResult;
 }