workaround for GCC 2.9x lacking std::char_traits<>::eof()

[SVN r29703]

include/boost/lexical_cast.hpp

@@ -154,7 +154,16 @@ namespace boost
             {
                 return !is_pointer<InputStreamable>::value &&
                        stream >> output &&
-                       stream.get() == std::char_traits<char_type>::eof();
+                       stream.get() ==
+#if defined(__GNUC__) && (__GNUC__<3) && defined(BOOST_NO_STD_WSTRING)
+// GCC 2.9x lacks std::char_traits<>::eof().
+// We use BOOST_NO_STD_WSTRING to filter out STLport and libstdc++-v3
+// configurations, which do provide std::char_traits<>::eof().
+    
+                           EOF;
+#else
+                           std::char_traits<char_type>::eof();
+#endif
             }
             bool operator>>(std::string &output)
             {