diff --git a/Astro/stars.hxx b/Astro/stars.hxx
index d2e70261b..212718d7e 100644
--- a/Astro/stars.hxx
+++ b/Astro/stars.hxx
@@ -40,7 +40,7 @@ int fgStarsInit( void );
 // Draw the Stars
 void fgStarsRender( void );
 
-extern struct OrbElements pltOrbElements[9];
+// [no longer used?] extern struct OrbElements pltOrbElements[9];
 extern fgTIME cur_time_params;
 
 
@@ -48,6 +48,9 @@ extern fgTIME cur_time_params;
 
 
 // $Log$
+// Revision 1.8  1999/01/19 20:57:00  curt
+// MacOS portability changes contributed by "Robert Puyol" <puyol@abvent.fr>
+//
 // Revision 1.7  1998/09/24 15:36:20  curt
 // Converted to c++ style comments.
 //
diff --git a/LaRCsim/ls_interface.c b/LaRCsim/ls_interface.c
index dc311d87f..09eda1ed1 100644
--- a/LaRCsim/ls_interface.c
+++ b/LaRCsim/ls_interface.c
@@ -222,7 +222,7 @@ $Original log: LaRCsim.c,v $
 
 --------------------------------------------------------------------------*/
 
-#include <sys/types.h>
+/* #include <sys/types.h> */
 /* #include <sys/stat.h> */
 #include <stdlib.h>
 #include <stdio.h>
@@ -574,6 +574,9 @@ int ls_ForceAltitude(double alt_feet) {
 /* Flight Gear Modification Log
  *
  * $Log$
+ * Revision 1.25  1999/01/19 20:57:02  curt
+ * MacOS portability changes contributed by "Robert Puyol" <puyol@abvent.fr>
+ *
  * Revision 1.24  1998/12/14 13:27:47  curt
  * Removed some old, outdated, no longer needed code.
  *
diff --git a/Main/GLUTmain.cxx b/Main/GLUTmain.cxx
index f1fba8050..83a73f42a 100644
--- a/Main/GLUTmain.cxx
+++ b/Main/GLUTmain.cxx
@@ -42,7 +42,9 @@
 #   include <stdlib.h>
 #endif
 
-#include <sys/stat.h> /* for stat() */
+#ifdef HAVE_SYS_STAT_H
+#  include <sys/stat.h> /* for stat() */
+#endif
 
 #ifdef HAVE_UNISTD_H
 #  include <unistd.h>    /* for stat() */
@@ -1000,6 +1002,9 @@ int main( int argc, char **argv ) {
 
 
 // $Log$
+// Revision 1.81  1999/01/19 20:57:03  curt
+// MacOS portability changes contributed by "Robert Puyol" <puyol@abvent.fr>
+//
 // Revision 1.80  1999/01/09 13:37:40  curt
 // Convert fgTIMESTAMP to FGTimeStamp which holds usec instead of ms.
 //
diff --git a/Main/fg_serial.cxx b/Main/fg_serial.cxx
index 601feb6c3..cfa7d6868 100644
--- a/Main/fg_serial.cxx
+++ b/Main/fg_serial.cxx
@@ -22,15 +22,20 @@
 // (Log is kept at end of this file)
 
 
-#include <stdlib.h>   // atoi()
+#include <Include/compiler.h>
 
-#include <string>
+#ifdef FG_HAVE_STD_INCLUDES
+#  include <cstdlib>    // atoi()
+#else
+#  include <stdlib.h>   // atoi()
+#endif
+
+#include STL_STRING
+#include STL_IOSTREAM                                           
 #include <vector>                                                               
 #include "Include/fg_stl_config.h"                                              
 
-#ifdef NEEDNAMESPACESTD                                                         
-using namespace std;                                                            
-#endif                                                                          
+FG_USING_NAMESPACE(std);
 
 #include <Aircraft/aircraft.hxx>
 #include <Debug/logstream.hxx>
@@ -451,6 +456,9 @@ void fgSerialProcess() {
 
 
 // $Log$
+// Revision 1.8  1999/01/19 20:57:04  curt
+// MacOS portability changes contributed by "Robert Puyol" <puyol@abvent.fr>
+//
 // Revision 1.7  1998/12/05 15:54:21  curt
 // Renamed class fgFLIGHT to class FGState as per request by JSB.
 //
diff --git a/Main/options.cxx b/Main/options.cxx
index 3d026eb9d..a963a4ff5 100644
--- a/Main/options.cxx
+++ b/Main/options.cxx
@@ -1,4 +1,3 @@
-//
 // options.cxx -- class to handle command line options
 //
 // Written by Curtis Olson, started April 1998.
@@ -630,6 +629,9 @@ fgOPTIONS::~fgOPTIONS( void ) {
 
 
 // $Log$
+// Revision 1.37  1999/01/19 20:57:05  curt
+// MacOS portability changes contributed by "Robert Puyol" <puyol@abvent.fr>
+//
 // Revision 1.36  1999/01/07 20:25:10  curt
 // Updated struct fgGENERAL to class FGGeneral.
 //
diff --git a/Main/options.hxx b/Main/options.hxx
index 994068b25..2d845a979 100644
--- a/Main/options.hxx
+++ b/Main/options.hxx
@@ -34,6 +34,8 @@
 #  include <config.h>
 #endif
 
+#include <Include/compiler.h>
+
 #ifdef HAVE_WINDOWS_H
 #  include <windows.h>
 #endif
@@ -41,16 +43,13 @@
 #include <GL/glut.h>
 #include <XGL/xgl.h>
 
-#include <string>
-#include <Include/compiler.h>
+#include STL_STRING
 FG_USING_STD(string);
 
 #include <vector>                                                               
 #include "Include/fg_stl_config.h"                                              
 
-#ifdef NEEDNAMESPACESTD                                                         
-using namespace std;                                                            
-#endif                                                                          
+FG_USING_NAMESPACE(std);
 
 #include "fg_serial.hxx"
 
@@ -247,6 +246,9 @@ extern fgOPTIONS current_options;
 
 
 // $Log$
+// Revision 1.25  1999/01/19 20:57:06  curt
+// MacOS portability changes contributed by "Robert Puyol" <puyol@abvent.fr>
+//
 // Revision 1.24  1998/11/25 01:34:01  curt
 // Support for an arbitrary number of serial ports.
 //
diff --git a/Time/fg_time.cxx b/Time/fg_time.cxx
index 24d130f13..c37c28752 100644
--- a/Time/fg_time.cxx
+++ b/Time/fg_time.cxx
@@ -28,6 +28,7 @@
 #endif
 
 #include "Include/compiler.h"
+
 #ifdef FG_HAVE_STD_INCLUDES
 #  include <cmath>
 #  include <cstdio>
@@ -398,6 +399,9 @@ void fgTimeUpdate(FGState *f, fgTIME *t) {
 
 
 // $Log$
+// Revision 1.29  1999/01/19 20:57:08  curt
+// MacOS portability changes contributed by "Robert Puyol" <puyol@abvent.fr>
+//
 // Revision 1.28  1999/01/07 20:25:34  curt
 // Portability changes and updates from Bernie Bright.
 //