diff --git a/Source/cmVisualStudio10TargetGenerator.cxx b/Source/cmVisualStudio10TargetGenerator.cxx
index ca6c41e26..d50bdde1f 100644
--- a/Source/cmVisualStudio10TargetGenerator.cxx
+++ b/Source/cmVisualStudio10TargetGenerator.cxx
@@ -997,6 +997,11 @@ WriteGroupSources(const char* name,
   this->WriteString("</ItemGroup>\n", 1);
 }
 
+void cmVisualStudio10TargetGenerator::WriteExtraSource(cmSourceFile const* sf)
+{
+  this->WriteSource("None", sf);
+}
+
 void cmVisualStudio10TargetGenerator::WriteSource(
   std::string const& tool, cmSourceFile const* sf, const char* end)
 {
@@ -1157,7 +1162,11 @@ void cmVisualStudio10TargetGenerator::WriteAllSources()
 
   std::vector<cmSourceFile const*> extraSources;
   this->GeneratorTarget->GetExtraSources(extraSources, "");
-  this->WriteSources("None", extraSources);
+  for(std::vector<cmSourceFile const*>::const_iterator
+        si = extraSources.begin(); si != extraSources.end(); ++si)
+    {
+    this->WriteExtraSource(*si);
+    }
 
   // Add object library contents as external objects.
   std::vector<std::string> objs;
diff --git a/Source/cmVisualStudio10TargetGenerator.h b/Source/cmVisualStudio10TargetGenerator.h
index 23d86dad7..8966f9374 100644
--- a/Source/cmVisualStudio10TargetGenerator.h
+++ b/Source/cmVisualStudio10TargetGenerator.h
@@ -57,6 +57,7 @@ private:
   void WriteProjectConfigurations();
   void WriteProjectConfigurationValues();
   void WriteMSToolConfigurationValues(std::string const& config);
+  void WriteExtraSource(cmSourceFile const* sf);
   void WriteSource(std::string const& tool, cmSourceFile const* sf,
                    const char* end = 0);
   void WriteSources(std::string const& tool,