diff --git a/doc/Doxyfile.in b/doc/Doxyfile.in
--- a/doc/Doxyfile.in
+++ b/doc/Doxyfile.in
@@ -221,7 +221,7 @@
 #---------------------------------------------------------------------------
 # Configuration options related to the dot tool   
 #---------------------------------------------------------------------------
-CLASS_DIAGRAMS         = NO
+CLASS_DIAGRAMS         = YES
 MSCGEN_PATH            = 
 HIDE_UNDOC_RELATIONS   = YES
 HAVE_DOT               = YES