diff --git a/wrap/gl/glu_tesselator.h b/wrap/gl/glu_tesselator.h
index e9f83ea7..9de33502 100644
--- a/wrap/gl/glu_tesselator.h
+++ b/wrap/gl/glu_tesselator.h
@@ -29,6 +29,19 @@
 #error "Please include OpenGL before including this file"
 #endif
 
+
+// The inclusion of glu should be always safe (if someone has already included gl stuff).
+#ifndef GLU_VERSIONS
+#ifdef __APPLE__
+#include <OpenGL/glu.h>
+#else
+#ifdef _WIN32
+  #include <windows.h>
+#endif
+#include <GL/glu.h>
+#endif
+#endif
+
 #ifndef CALLBACK
 #ifdef _WIN32
 #define CALLBACK __stdcall
diff --git a/wrap/gl/picking.h b/wrap/gl/picking.h
index 77007497..c1581b34 100644
--- a/wrap/gl/picking.h
+++ b/wrap/gl/picking.h
@@ -50,6 +50,18 @@ Revision 1.1  2005/12/03 09:36:28  ganovelli
 #define WRAP_GL_PICKING_H
 
 #include <algorithm>
+
+#ifndef GLU_VERSIONS
+#ifdef __APPLE__
+#include <OpenGL/glu.h>
+#else
+#ifdef _WIN32
+  #include <windows.h>
+#endif
+#include <GL/glu.h>
+#endif
+#endif
+
 namespace vcg
 {