diff --git a/juce_amalgamated.cpp b/juce_amalgamated.cpp
index 019a7f771b..e9b9d9b484 100644
--- a/juce_amalgamated.cpp
+++ b/juce_amalgamated.cpp
@@ -11784,7 +11784,7 @@ String::String (const CharPointer_UTF32& start, const CharPointer_UTF32& end) :
 
 const String String::charToString (const juce_wchar character)
 {
-	String result (PreallocationBytes (sizeof (CharPointerType::CharType)));
+	String result (PreallocationBytes (CharPointerType::getBytesRequiredFor (character)));
 	CharPointerType t (result.text);
 	t.write (character);
 	t.writeNull();
diff --git a/src/text/juce_String.cpp b/src/text/juce_String.cpp
index a5f93fb47d..525ea04620 100644
--- a/src/text/juce_String.cpp
+++ b/src/text/juce_String.cpp
@@ -318,7 +318,7 @@ String::String (const CharPointer_UTF32& start, const CharPointer_UTF32& end) :
 
 const String String::charToString (const juce_wchar character)
 {
-    String result (PreallocationBytes (sizeof (CharPointerType::CharType)));
+    String result (PreallocationBytes (CharPointerType::getBytesRequiredFor (character)));
     CharPointerType t (result.text);
     t.write (character);
     t.writeNull();