diff --git a/nel/include/nel/misc/common.h b/nel/include/nel/misc/common.h
index 7b89bae3b..2f678acef 100644
--- a/nel/include/nel/misc/common.h
+++ b/nel/include/nel/misc/common.h
@@ -227,8 +227,8 @@ inline double	isValidDouble (double v)
  * \param str a string to transform to lower case
  */
 
-std::string toLower ( const char *str ); // UTF-8
-std::string	toLower ( const std::string &str ); // UTF-8
+std::string toLower ( const char *str ); // Ascii only
+std::string	toLower ( const std::string &str ); // Ascii only
 void		toLower ( char *str ); // Ascii only
 char		toLower ( const char ch );	// convert only one character
 
@@ -236,8 +236,8 @@ char		toLower ( const char ch );	// convert only one character
  * \param a string to transform to upper case
  */
 
-std::string toUpper ( const char *str ); // UTF-8
-std::string	toUpper ( const std::string &str); // UTF-8
+// std::string toUpper ( const char *str ); // Ascii only
+std::string	toUpper ( const std::string &str); // Ascii only
 void		toUpper ( char *str); // Ascii only
 
 
diff --git a/nel/include/nel/misc/ucstring.h b/nel/include/nel/misc/ucstring.h
index 61f7f416b..8bbcd828d 100644
--- a/nel/include/nel/misc/ucstring.h
+++ b/nel/include/nel/misc/ucstring.h
@@ -260,6 +260,12 @@ ucstring toUpper(const ucstring &str);
 void toUpper(ucchar *str);
 ucchar toUpper(ucchar c);
 
+std::string toLowerAsUtf8(const char *str);
+std::string	toLowerAsUtf8(const std::string &str);
+
+std::string toUpperAsUtf8(const char *str);
+std::string	toUpperAsUtf8(const std::string &str);
+
 };
 
 #endif // NL_UCSTRING_H
diff --git a/nel/src/gui/string_case.cpp b/nel/src/gui/string_case.cpp
index f6218d39a..d970d1e03 100644
--- a/nel/src/gui/string_case.cpp
+++ b/nel/src/gui/string_case.cpp
@@ -148,10 +148,10 @@ namespace NLGUI
 		switch (mode)
 		{
 		case CaseLower:
-			str = NLMISC::toLower(str);
+			str = NLMISC::toLowerAsUtf8(str);
 			break;
 		case CaseUpper:
-			str = NLMISC::toUpper(str);
+			str = NLMISC::toUpperAsUtf8(str);
 			break;
 		case CaseFirstStringLetterUp:
 		{
diff --git a/nel/src/misc/common.cpp b/nel/src/misc/common.cpp
index c1bf67efa..b9e9a7d85 100644
--- a/nel/src/misc/common.cpp
+++ b/nel/src/misc/common.cpp
@@ -594,7 +594,6 @@ NLMISC_CATEGORISED_COMMAND(nel,stohr, "Convert a second number into an human rea
 	return true;
 }
 
-/*
 std::string toLower(const char *str)
 {
 	if (!str) return "";
@@ -625,7 +624,6 @@ std::string	toLower(const std::string &str)
 	}
 	return res;
 }
-*/
 
 char toLower(const char ch)
 {
@@ -654,7 +652,6 @@ void toLower(char *str)
 	}
 }
 
-/*
 std::string toUpper(const std::string &str)
 {
 	string res;
@@ -668,7 +665,6 @@ std::string toUpper(const std::string &str)
 	}
 	return res;
 }
-*/
 
 void toUpper(char *str)
 {
diff --git a/nel/src/misc/unicode.cpp b/nel/src/misc/unicode.cpp
index 12dfdcad4..6a0bf25c0 100644
--- a/nel/src/misc/unicode.cpp
+++ b/nel/src/misc/unicode.cpp
@@ -1950,7 +1950,7 @@ ucchar		toLower (ucchar c)
 
 // ***************************************************************************
 
-static std::string toLower(CUtfStringView sv)
+static std::string toLowerAsUtf8(CUtfStringView sv)
 {
 	std::string res;
 	res.reserve(sv.largestSize());
@@ -1962,23 +1962,23 @@ static std::string toLower(CUtfStringView sv)
 			ucchar uc = c;
 			ucchar *result = toLowerUpperSearch(&uc, UnicodeUpperToLower);
 			if (result)
-				c = uc;
+				c = result[1];
 		}
 		CUtfStringView::append(res, c);
 	}
 	return res;
 }
 
-std::string toLower(const char *str)
+std::string toLowerAsUtf8(const char *str)
 {
-	return toLower(CUtfStringView(str));
+	return toLowerAsUtf8(CUtfStringView(str));
 }
 
 // ***************************************************************************
 
-std::string	toLower(const std::string &str)
+std::string	toLowerAsUtf8(const std::string &str)
 {
-	return toLower(CUtfStringView(str));
+	return toLowerAsUtf8(CUtfStringView(str));
 }
 
 // ***************************************************************************
@@ -2025,7 +2025,7 @@ ucchar		toUpper (ucchar c)
 
 // ***************************************************************************
 
-static std::string toUpper(CUtfStringView sv)
+static std::string toUpperAsUtf8(CUtfStringView sv)
 {
 	std::string res;
 	res.reserve(sv.largestSize());
@@ -2037,23 +2037,23 @@ static std::string toUpper(CUtfStringView sv)
 			ucchar uc = c;
 			ucchar *result = toLowerUpperSearch(&uc, UnicodeLowerToUpper);
 			if (result)
-				c = uc;
+				c = result[1];
 		}
 		CUtfStringView::append(res, c);
 	}
 	return res;
 }
 
-std::string toUpper(const char *str)
+std::string toUpperAsUtf8(const char *str)
 {
-	return toUpper(CUtfStringView(str));
+	return toUpperAsUtf8(CUtfStringView(str));
 }
 
 // ***************************************************************************
 
-std::string	toUpper(const std::string &str)
+std::string	toUpperAsUtf8(const std::string &str)
 {
-	return toUpper(CUtfStringView(str));
+	return toUpperAsUtf8(CUtfStringView(str));
 }
 
 // ***************************************************************************