diff --git a/projects/VC90/SimGear.vcproj b/projects/VC90/SimGear.vcproj
index fca9e993..2db0dcc5 100644
--- a/projects/VC90/SimGear.vcproj
+++ b/projects/VC90/SimGear.vcproj
@@ -641,6 +641,14 @@
 				RelativePath="..\..\simgear\misc\sg_dir.hxx"
 				>
 			</File>
+			<File
+				RelativePath="..\..\simgear\misc\sg_sleep.cxx"
+				>
+			</File>
+			<File
+				RelativePath="..\..\simgear\misc\sg_sleep.hxx"
+				>
+			</File>
 			<File
 				RelativePath="..\..\simgear\misc\sg_path.cxx"
 				>
diff --git a/simgear/compiler.h b/simgear/compiler.h
index 6a9ec5d8..372f571d 100644
--- a/simgear/compiler.h
+++ b/simgear/compiler.h
@@ -109,6 +109,7 @@
 
 
 #if defined (__sun)
+#  define SG_UNIX
 #  include <strings.h>
 #  include <memory.h>
 #  if defined ( __cplusplus )
@@ -138,6 +139,8 @@
 //
 
 #ifdef __APPLE__
+#  define SG_MAC
+#  define SG_UNIX
 #  ifdef __GNUC__
 #    if ( __GNUC__ > 3 ) || ( __GNUC__ == 3 && __GNUC_MINOR__ >= 3 )
 inline int (isnan)(double r) { return !(r <= 0 || r >= 0); }
@@ -154,6 +157,7 @@ inline int (isnan)(double r) { return !(r <= 0 || r >= 0); }
 #endif
 
 #if defined (__FreeBSD__)
+#  define SG_UNIX
 #include <sys/param.h>
 #  if __FreeBSD_version < 500000
      extern "C" {
@@ -163,9 +167,19 @@ inline int (isnan)(double r) { return !(r <= 0 || r >= 0); }
 #endif
 
 #if defined (__CYGWIN__)
+#  define SG_WINDOWS
+#  define SG_UNIX
 #  include <ieeefp.h>		// isnan
 #endif
 
+// includes both MSVC and mingw compilers
+#if defined(_WIN32) || defined(__WIN32__)
+#  define SG_WINDOWS
+#endif
+
+#if defined(__linux__) || defined(_AIX) || defined ( sgi )
+#  define SG_UNIX
+#endif
 
 //
 // No user modifiable definitions beyond here.
diff --git a/simgear/misc/Makefile.am b/simgear/misc/Makefile.am
index 4a4b1fb6..ae696e79 100644
--- a/simgear/misc/Makefile.am
+++ b/simgear/misc/Makefile.am
@@ -14,7 +14,8 @@ include_HEADERS = \
 	stdint.hxx \
 	PathOptions.hxx \
 	sg_dir.hxx \
-	ResourceManager.hxx 
+	ResourceManager.hxx \
+	sg_sleep.hxx
 
 libsgmisc_a_SOURCES = \
 	sg_path.cxx \
@@ -26,7 +27,8 @@ libsgmisc_a_SOURCES = \
 	interpolator.cxx \
 	PathOptions.cxx \
 	sg_dir.cxx \
-	ResourceManager.cxx 
+	ResourceManager.cxx \
+	sg_sleep.cxx
 
 #noinst_PROGRAMS = tabbed_value_test swap_test
 
diff --git a/simgear/misc/sg_sleep.cxx b/simgear/misc/sg_sleep.cxx
new file mode 100644
index 00000000..a52880c5
--- /dev/null
+++ b/simgear/misc/sg_sleep.cxx
@@ -0,0 +1,60 @@
+
+// Written by James Turner, started July 2010.
+//
+// Copyright (C) 2010  Curtis L. Olson - http://www.flightgear.org/~curt
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Library General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+//
+// $Id$
+
+#include <simgear/misc/sg_sleep.hxx>
+
+#ifdef SG_WINDOWS
+# include <windows.h>
+#else
+# include <unistd.h>
+#endif
+
+namespace simgear
+{
+
+#ifdef SG_WINDOWS
+
+void sleepForSeconds(int seconds)
+{
+  Sleep(1000 * seconds);
+}
+
+void sleepForMSec(int msec)
+{
+  Sleep(msec);
+}
+
+#else
+
+void sleepForSeconds(int seconds)
+{
+  ::sleep(seconds);
+}
+
+void sleepForMSec(int msec)
+{
+  ::usleep(msec * 1000);
+}
+
+#endif
+
+} // of namespace simhear
+
diff --git a/simgear/misc/sg_sleep.hxx b/simgear/misc/sg_sleep.hxx
new file mode 100644
index 00000000..389fdff3
--- /dev/null
+++ b/simgear/misc/sg_sleep.hxx
@@ -0,0 +1,41 @@
+
+// Written by James Turner, started July 2010.
+//
+// Copyright (C) 2010  Curtis L. Olson - http://www.flightgear.org/~curt
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Library General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+//
+// $Id$
+
+
+#ifndef _SG_SLEEP_HXX
+#define _SG_SLEEP_HXX
+
+
+#include <simgear/compiler.h>
+
+
+namespace simgear
+{
+
+void sleepForSeconds(int seconds);
+
+void sleepForMSec(int msec);
+
+} // of namespace simgear
+
+#endif // _SG_SLEEP_HXX
+
+