diff --git a/src/osgPlugins/osgjs/json_stream b/src/osgPlugins/osgjs/json_stream
index 45109d960..028dee84f 100644
--- a/src/osgPlugins/osgjs/json_stream
+++ b/src/osgPlugins/osgjs/json_stream
@@ -10,6 +10,7 @@
 #include <cmath>
 #include <limits>
 
+using namespace std;
 
 // A simple class wrapping ofstream calls to enable generic cleaning of json data.
 // Especially 'standard' json should:
@@ -66,11 +67,11 @@ class json_stream : public std::ofstream {
         }
 
         double to_valid_float(const double d) {
-            if(std::isfinite(d)) {
+            if(isfinite(d)) {
                 return d;
             }
             else {
-                if(std::isinf(d)) {
+                if(isinf(d)) {
                     return std::numeric_limits<double>::max();
                 }
                 // no much way to do better than replace invalid float NaN by 0