diff --git a/include/mapnik/json/symbolizer_grammar.hpp b/include/mapnik/json/symbolizer_grammar.hpp
index 040d6e1c3..89a0cf25f 100644
--- a/include/mapnik/json/symbolizer_grammar.hpp
+++ b/include/mapnik/json/symbolizer_grammar.hpp
@@ -30,6 +30,7 @@
 
 // mapnik
 #include <mapnik/symbolizer.hpp>
+#include <mapnik/symbolizer_utils.hpp>
 #include <mapnik/json/generic_json.hpp>
 
 namespace mapnik { namespace json {
@@ -63,8 +64,7 @@ struct json_value_visitor : boost::static_visitor<>
 
     void operator() (std::string const& val) const
     {
-        std::cerr << std::get<0>(get_meta(key_)) << ":" << val <<  std::endl;
-        put<std::string>(sym_, key_, val);
+        set_property(sym_, key_, val);
     }
 
     template <typename T>
diff --git a/include/mapnik/symbolizer_utils.hpp b/include/mapnik/symbolizer_utils.hpp
index 4ec6c69e6..5d57431cd 100644
--- a/include/mapnik/symbolizer_utils.hpp
+++ b/include/mapnik/symbolizer_utils.hpp
@@ -24,9 +24,10 @@
 #define MAPNIK_SYMBOLIZER_UTILS_HPP
 
 // mapnik
-#include <mapnik/symbolizer.hpp>
-#include <mapnik/transform_processor.hpp>
 #include <mapnik/expression_string.hpp>
+#include <mapnik/transform_processor.hpp>
+#include <mapnik/color_factory.hpp>
+#include <mapnik/symbolizer.hpp>
 
 // boost
 #include <boost/variant/apply_visitor.hpp>
@@ -180,7 +181,7 @@ public:
         std::ostringstream ss;
         if (expr)
         {
-            ss << '\"' << mapnik::to_expression_string(*expr) <<  '\"';
+            ss << '\"' << "FIXME" /*mapnik::to_expression_string(*expr)*/ <<  '\"';
         }
         return ss.str();
     }
@@ -239,6 +240,67 @@ struct symbolizer_to_json : public boost::static_visitor<std::string>
     }
 };
 
+namespace {
+
+template <typename Symbolizer, typename T>
+struct set_property_impl
+{
+    static void apply(Symbolizer & sym, mapnik::keys key, std::string const& val)
+    {
+        std::cerr << "do nothing" << std::endl;
+    }
+};
+
+template <typename Symbolizer>
+struct set_property_impl<Symbolizer, std::integral_constant<property_types, property_types::target_color> >
+{
+    static void apply(Symbolizer & sym, mapnik::keys key, std::string const& val)
+    {
+        put(sym, key, mapnik::parse_color(val));
+    }
+};
+
+template <typename Symbolizer>
+struct set_property_impl<Symbolizer, std::integral_constant<property_types, property_types::target_double> >
+{
+    static void apply(Symbolizer & sym, mapnik::keys key, std::string const& val)
+    {
+        std::cerr << " expects double" << std::endl;
+    }
+};
+
+template <typename Symbolizer>
+struct set_property_impl<Symbolizer, std::integral_constant<property_types, property_types::target_bool> >
+{
+    static void apply(Symbolizer & sym, mapnik::keys key, std::string const& val)
+    {
+        std::cerr << " expects bool" << std::endl;
+    }
+};
+
+}
+
+template <typename Symbolizer, typename T>
+inline void set_property(Symbolizer & sym, mapnik::keys key, T const& val)
+{
+    switch (std::get<3>(get_meta(key)))
+    {
+    case property_types::target_bool:
+        set_property_impl<Symbolizer, std::integral_constant<property_types, property_types::target_bool> >::apply(sym,key,val);
+        break;
+    case property_types::target_integer:
+        set_property_impl<Symbolizer, std::integral_constant<property_types, property_types::target_integer> >::apply(sym,key,val);
+        break;
+    case property_types::target_double:
+        set_property_impl<Symbolizer, std::integral_constant<property_types, property_types::target_double> >::apply(sym,key,val);
+        break;
+    case property_types::target_color:
+        set_property_impl<Symbolizer, std::integral_constant<property_types, property_types::target_color> >::apply(sym,key,val);
+        break;
+    default:
+        break;
+    }
+}
 
 }