diff --git a/src/support/convert.cpp b/src/support/convert.cpp
index 9c69abbce6..70cd91eeba 100644
--- a/src/support/convert.cpp
+++ b/src/support/convert.cpp
@@ -17,6 +17,7 @@
 #include <boost/lexical_cast.hpp>
 
 #include <string>
+//needed for Mac OSX 10.5.2 Leopard
 #include <cstdlib>
 
 using namespace std;
diff --git a/src/support/docstring.cpp b/src/support/docstring.cpp
index 9883425ab2..dfbaab7bd5 100644
--- a/src/support/docstring.cpp
+++ b/src/support/docstring.cpp
@@ -19,6 +19,7 @@
 
 #include <QFile>
 
+//Needed in Ubuntu
 #include <typeinfo>
 #if ! defined(USE_WCHAR_T) && defined(__GNUC__)
 #include <locale>
diff --git a/src/support/socktools.cpp b/src/support/socktools.cpp
index 0b20940afe..d4aab38f5f 100644
--- a/src/support/socktools.cpp
+++ b/src/support/socktools.cpp
@@ -51,6 +51,7 @@ int accept(int)
 
 #include <cerrno>
 #include <string>
+//needed for Mac OSX 10.5.2 Leopard
 #include <cstring>
 
 using namespace std;
diff --git a/src/support/unicode.cpp b/src/support/unicode.cpp
index 8b0f9cb0db..36cb1800f2 100644
--- a/src/support/unicode.cpp
+++ b/src/support/unicode.cpp
@@ -23,6 +23,7 @@
 #include <cerrno>
 #include <map>
 #include <ostream>
+//Needed in MSVC
 #include <string>