diff --git a/Modules/Wrappers/SWIG/src/python/otbPythonLogOutput.cxx b/Modules/Wrappers/SWIG/src/python/otbPythonLogOutput.cxx
index a924de7a165950cc42e840de268f4fc989a4da14..6a36c88c4cb8a2f99532188d068d718c3d623287 100644
--- a/Modules/Wrappers/SWIG/src/python/otbPythonLogOutput.cxx
+++ b/Modules/Wrappers/SWIG/src/python/otbPythonLogOutput.cxx
@@ -34,6 +34,8 @@ void PythonLogOutput::Write(double timestamp)
 
 void PythonLogOutput::Write(std::string const& content)
 {
+  // Note : Reacuiring the GIL before calling the callback doesn' seems to be
+  // necessary with thread=1 and director classes
   m_Callback->Call(content);
 }