diff --git a/gl/Module.mk b/gl/Module.mk
index 590883b977bc0072b52cbf4289d33098c2f710df..9c48482dcb1ccc203cdd4512c7f52c7d8e822a4f 100644
--- a/gl/Module.mk
+++ b/gl/Module.mk
@@ -18,6 +18,12 @@ ifeq ($(ARCH),win32)
 GLS          += TWin32GLKernel.cxx TWin32GLViewerImp.cxx
 else
 GLS          += TRootGLKernel.cxx TRootGLViewer.cxx
+ifneq ($(IVROOT),)
+GLS          += TRootOIViewer.cxx
+IVLIBDIR     := -L$(IVROOT)/usr/lib
+IVLIB        := -lInventor -lInventorXt -lXm -lXt -lXext -lX11
+IVINCDIR     := $(IVROOT)/usr/include
+endif
 endif
 GLS          := $(patsubst %,$(MODDIRS)/%,$(GLS))
 
@@ -38,9 +44,16 @@ INCLUDEFILES += $(GLDEP)
 include/%.h:    $(GLDIRI)/%.h
 		cp $< $@
 
+ifneq ($(IVROOT),)
+$(GLLIB):       $(GLO) $(MAINLIBS) $(GLLIBDEP)
+		@$(MAKELIB) $(PLATFORM) $(LD) "$(LDFLAGS)" \
+		   "$(SOFLAGS)" libRGL.$(SOEXT) $@ "$(GLO)" \
+		   "$(GLLIBEXTRA) $(IVLIBDIR) $(IVLIB)"
+else
 $(GLLIB):       $(GLO) $(MAINLIBS) $(GLLIBDEP)
 		@$(MAKELIB) $(PLATFORM) $(LD) "$(LDFLAGS)" \
 		   "$(SOFLAGS)" libRGL.$(SOEXT) $@ "$(GLO)" "$(GLLIBEXTRA)"
+endif
 
 all-gl:         $(GLLIB)
 
@@ -55,5 +68,12 @@ distclean-gl:   clean-gl
 distclean::     distclean-gl
 
 ##### extra rules ######
+ifneq ($(IVROOT),)
+$(GLO): %.o: %.cxx
+	$(CXX) $(OPT) -DR__OPENINVENTOR $(CXXFLAGS) -I$(OPENGLINCDIR) \
+	   -I$(IVINCDIR) -o $@ -c $<
+else
 $(GLO): %.o: %.cxx
 	$(CXX) $(OPT) $(CXXFLAGS) -I$(OPENGLINCDIR) -o $@ -c $<
+endif
+
diff --git a/gl/src/TRootGLKernel.cxx b/gl/src/TRootGLKernel.cxx
index 6d97f9d9ff91f8c5bbbdd66821d406e194b649b6..4f161faaf4a01fc08c143afabf8c29062862a44e 100644
--- a/gl/src/TRootGLKernel.cxx
+++ b/gl/src/TRootGLKernel.cxx
@@ -1,4 +1,4 @@
-// @(#)root/gl:$Name$:$Id$
+// @(#)root/gl:$Name:  $:$Id: TRootGLKernel.cxx,v 1.1.1.1 2000/05/16 17:00:47 rdm Exp $
 // Author: Fons Rademakers   04/03/98
 
 /*************************************************************************
@@ -19,7 +19,11 @@
 //////////////////////////////////////////////////////////////////////////
 
 #include "TRootGLKernel.h"
+#ifndef R__OPENINVENTOR
 #include "TRootGLViewer.h"
+#else
+#include "TRootOIViewer.h"
+#endif
 
 
 // Force creation of TRootGLKernel when shared library will be loaded.
@@ -30,5 +34,9 @@ static TRootGLKernel gGLKernelCreator;
 TGLViewerImp *TRootGLKernel::CreateGLViewerImp(TPadOpenGLView *p, const char *title,
                                                UInt_t width, UInt_t height)
 {
+#ifndef R__OPENINVENTOR
    return new TRootGLViewer(p, title, width, height);
+#else
+   return new TRootOIViewer(p, title, width, height);
+#endif
 }