diff --git a/string/public/nsReadableUtils.h b/string/public/nsReadableUtils.h
index b8b5fe0df3af..b684e20255fc 100755
--- a/string/public/nsReadableUtils.h
+++ b/string/public/nsReadableUtils.h
@@ -47,11 +47,11 @@ NS_COM size_t Distance( const nsReadingIterator<char>&, const nsReadingIterator<
 
 NS_COM void CopyUCS2toASCII( const nsAString& aSource, nsACString& aDest );
 NS_COM void CopyASCIItoUCS2( const nsACString& aSource, nsAString& aDest );
-NS_COM void CopyUCS2toUTF8( const nsAString& aSource, nsACString& aDest );
-NS_COM void CopyUTF8toUCS2( const nsACString& aSource, nsAString& aDest );
+NS_COM void CopyUTF16toUTF8( const nsAString& aSource, nsACString& aDest );
+NS_COM void CopyUTF8toUTF16( const nsACString& aSource, nsAString& aDest );
 
-NS_COM void AppendUCS2toUTF8( const nsAString& aSource, nsACString& aDest );
-NS_COM void AppendUTF8toUCS2( const nsACString& aSource, nsAString& aDest );
+NS_COM void AppendUTF16toUTF8( const nsAString& aSource, nsACString& aDest );
+NS_COM void AppendUTF8toUTF16( const nsACString& aSource, nsAString& aDest );
 
   /**
    * Returns a new |char| buffer containing a zero-terminated copy of |aSource|.
diff --git a/string/src/nsReadableUtils.cpp b/string/src/nsReadableUtils.cpp
index 6c6d8ca699cb..873e1bcfc50b 100755
--- a/string/src/nsReadableUtils.cpp
+++ b/string/src/nsReadableUtils.cpp
@@ -178,23 +178,23 @@ CopyASCIItoUCS2( const nsACString& aSource, nsAString& aDest )
 
 NS_COM
 void
-CopyUCS2toUTF8( const nsAString& aSource, nsACString& aDest )
+CopyUTF16toUTF8( const nsAString& aSource, nsACString& aDest )
   {
     aDest.Truncate();
-    AppendUCS2toUTF8(aSource, aDest);
+    AppendUTF16toUTF8(aSource, aDest);
   }
 
 NS_COM
 void
-CopyUTF8toUCS2( const nsACString& aSource, nsAString& aDest )
+CopyUTF8toUTF16( const nsACString& aSource, nsAString& aDest )
   {
     aDest.Truncate();
-    AppendUTF8toUCS2(aSource, aDest);
+    AppendUTF8toUTF16(aSource, aDest);
   }
 
 NS_COM
 void
-AppendUCS2toUTF8( const nsAString& aSource, nsACString& aDest )
+AppendUTF16toUTF8( const nsAString& aSource, nsACString& aDest )
   {
     // This isn't the fastest possible implementation of this method,
     // but it works, and that's better than nothing!
@@ -204,7 +204,7 @@ AppendUCS2toUTF8( const nsAString& aSource, nsACString& aDest )
 
 NS_COM
 void
-AppendUTF8toUCS2( const nsACString& aSource, nsAString& aDest )
+AppendUTF8toUTF16( const nsACString& aSource, nsAString& aDest )
   {
     // This isn't the fastest possible implementation of this method,
     // but it works, and that's better than nothing!
diff --git a/xpcom/string/public/nsReadableUtils.h b/xpcom/string/public/nsReadableUtils.h
index b8b5fe0df3af..b684e20255fc 100755
--- a/xpcom/string/public/nsReadableUtils.h
+++ b/xpcom/string/public/nsReadableUtils.h
@@ -47,11 +47,11 @@ NS_COM size_t Distance( const nsReadingIterator<char>&, const nsReadingIterator<
 
 NS_COM void CopyUCS2toASCII( const nsAString& aSource, nsACString& aDest );
 NS_COM void CopyASCIItoUCS2( const nsACString& aSource, nsAString& aDest );
-NS_COM void CopyUCS2toUTF8( const nsAString& aSource, nsACString& aDest );
-NS_COM void CopyUTF8toUCS2( const nsACString& aSource, nsAString& aDest );
+NS_COM void CopyUTF16toUTF8( const nsAString& aSource, nsACString& aDest );
+NS_COM void CopyUTF8toUTF16( const nsACString& aSource, nsAString& aDest );
 
-NS_COM void AppendUCS2toUTF8( const nsAString& aSource, nsACString& aDest );
-NS_COM void AppendUTF8toUCS2( const nsACString& aSource, nsAString& aDest );
+NS_COM void AppendUTF16toUTF8( const nsAString& aSource, nsACString& aDest );
+NS_COM void AppendUTF8toUTF16( const nsACString& aSource, nsAString& aDest );
 
   /**
    * Returns a new |char| buffer containing a zero-terminated copy of |aSource|.
diff --git a/xpcom/string/src/nsReadableUtils.cpp b/xpcom/string/src/nsReadableUtils.cpp
index 6c6d8ca699cb..873e1bcfc50b 100755
--- a/xpcom/string/src/nsReadableUtils.cpp
+++ b/xpcom/string/src/nsReadableUtils.cpp
@@ -178,23 +178,23 @@ CopyASCIItoUCS2( const nsACString& aSource, nsAString& aDest )
 
 NS_COM
 void
-CopyUCS2toUTF8( const nsAString& aSource, nsACString& aDest )
+CopyUTF16toUTF8( const nsAString& aSource, nsACString& aDest )
   {
     aDest.Truncate();
-    AppendUCS2toUTF8(aSource, aDest);
+    AppendUTF16toUTF8(aSource, aDest);
   }
 
 NS_COM
 void
-CopyUTF8toUCS2( const nsACString& aSource, nsAString& aDest )
+CopyUTF8toUTF16( const nsACString& aSource, nsAString& aDest )
   {
     aDest.Truncate();
-    AppendUTF8toUCS2(aSource, aDest);
+    AppendUTF8toUTF16(aSource, aDest);
   }
 
 NS_COM
 void
-AppendUCS2toUTF8( const nsAString& aSource, nsACString& aDest )
+AppendUTF16toUTF8( const nsAString& aSource, nsACString& aDest )
   {
     // This isn't the fastest possible implementation of this method,
     // but it works, and that's better than nothing!
@@ -204,7 +204,7 @@ AppendUCS2toUTF8( const nsAString& aSource, nsACString& aDest )
 
 NS_COM
 void
-AppendUTF8toUCS2( const nsACString& aSource, nsAString& aDest )
+AppendUTF8toUTF16( const nsACString& aSource, nsAString& aDest )
   {
     // This isn't the fastest possible implementation of this method,
     // but it works, and that's better than nothing!