diff --git a/include/boost/date_time/gregorian/greg_month.hpp b/include/boost/date_time/gregorian/greg_month.hpp
index d483f774..3bf1f3da 100644
--- a/include/boost/date_time/gregorian/greg_month.hpp
+++ b/include/boost/date_time/gregorian/greg_month.hpp
@@ -52,7 +52,7 @@ namespace gregorian {
 
   
   //! Wrapper class to represent months in gregorian based calendar
-  class BOOST_DATE_TIME_DECL greg_month : public greg_month_rep {
+  class greg_month : public greg_month_rep {
   public:
     typedef date_time::months_of_year month_enum;
     typedef std::map<std::string, unsigned short> month_map_type;
@@ -67,14 +67,14 @@ namespace gregorian {
     //! Returns month as number from 1 to 12
     unsigned short as_number() const {return value_;}
     month_enum as_enum() const {return static_cast<month_enum>(value_);}
-    const char* as_short_string() const;
-    const char* as_long_string()  const;
+    const char* as_short_string() const { return as_short_string_impl(value_); }
+    const char* as_long_string()  const { return as_long_string_impl(value_); }
 #ifndef BOOST_NO_STD_WSTRING
-    const wchar_t* as_short_wstring() const;
-    const wchar_t* as_long_wstring()  const;
+    const wchar_t* as_short_wstring() const { return as_short_wstring_impl(value_); }
+    const wchar_t* as_long_wstring()  const { return as_long_wstring_impl(value_); }
 #endif // BOOST_NO_STD_WSTRING
     //! Shared pointer to a map of Month strings (Names & Abbrev) & numbers
-    static month_map_ptr_type get_month_map_ptr();
+    static BOOST_DATE_TIME_DECL month_map_ptr_type get_month_map_ptr();
 
     /* parameterized as_*_string functions are intended to be called
      * from a template function: "... as_short_string(charT c='\0');" */
@@ -96,6 +96,13 @@ namespace gregorian {
       return as_long_wstring();
     }
 #endif // BOOST_NO_STD_WSTRING
+  protected:
+    static BOOST_DATE_TIME_DECL const char* as_short_string_impl(greg_month_rep value);
+    static BOOST_DATE_TIME_DECL const char* as_long_string_impl(greg_month_rep value);
+#ifndef BOOST_NO_STD_WSTRING
+    static BOOST_DATE_TIME_DECL const wchar_t* as_short_wstring_impl(greg_month_rep value);
+    static BOOST_DATE_TIME_DECL const wchar_t* as_long_wstring_impl(greg_month_rep value);
+#endif // BOOST_NO_STD_WSTRING
   };
 
 } } //namespace gregorian
diff --git a/src/gregorian/greg_month.cpp b/src/gregorian/greg_month.cpp
index 8232378c..5a5c65ea 100644
--- a/src/gregorian/greg_month.cpp
+++ b/src/gregorian/greg_month.cpp
@@ -54,16 +54,16 @@ namespace gregorian {
 
   //! Returns 3 char english string for the month ex: Jan, Feb, Mar, Apr
   const char*
-  greg_month::as_short_string() const 
+  greg_month::as_short_string_impl(greg_month_rep value)
   {
-    return short_month_names[value_-1];
+    return short_month_names[value-1];
   }
   
   //! Returns full name of month as string in english ex: January, February
   const char*
-  greg_month::as_long_string()  const 
+  greg_month::as_long_string_impl(greg_month_rep value)
   {
-    return long_month_names[value_-1];
+    return long_month_names[value-1];
   }
  
   //! Return special_value from string argument
@@ -87,16 +87,16 @@ namespace gregorian {
 #ifndef BOOST_NO_STD_WSTRING
   //! Returns 3 wchar_t english string for the month ex: Jan, Feb, Mar, Apr
   const wchar_t*
-  greg_month::as_short_wstring() const 
+  greg_month::as_short_wstring_impl(greg_month_rep value)
   {
-    return w_short_month_names[value_-1];
+    return w_short_month_names[value-1];
   }
   
   //! Returns full name of month as wchar_t string in english ex: January, February
   const wchar_t*
-  greg_month::as_long_wstring()  const 
+  greg_month::as_long_wstring_impl(greg_month_rep value)
   {
-    return w_long_month_names[value_-1];
+    return w_long_month_names[value-1];
   }
 #endif // BOOST_NO_STD_WSTRING