diff --git a/ChangeLog b/ChangeLog
index 1e0f416dc..16985d9f2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,16 +1,21 @@
-2003-09-25  Rachid REBIHA  <rebiha@nyx>
+2003-09-30  Alexandre Duret-Lutz  <aduret@src.lip6.fr>
 
-	* src/tgbatest/emptinesscheckexplicit.test (acc): New file.
+	* src/tgba/state.hh (state_ptr_less_than, state_ptr_equal):
+	Declare as std::binary_function.
+	(state_ptr_hash): Declare as std::unary_function.
+	* src/tgbaalgos/lbtt.cc (state_acc_pair_equal,
+	state_acc_pair_hash): Likewise.
+	* src/misc/bddlt.hh (bdd_less_than): Likewise.
+	* src/misc/hash.hh (ptr_hash, string_hash): Likewise.
 
-	* src/tgbatest/emptinesscheckexplicit.cc (main): New file.
+2003-09-25  Rachid REBIHA  <rebiha@src.lip6.fr>
 
-	* src/tgbatest/emptinesscheck.test: New file.
-
-	* src/tgbatest/emptinesscheck.cc (main): New file.
-
-	* src/tgbaalgos/emptinesscheck.cc (spot): New method.
-
-	* src/tgbaalgos/emptinesscheck.hh: New interface.
+	* src/tgbatest/emptinesscheckexplicit.test,
+	src/tgbatest/emptinesscheckexplicit.cc
+	src/tgbatest/emptinesscheck.test,
+	src/tgbatest/emptinesscheck.cc,
+	src/tgbaalgos/emptinesscheck.cc,
+	src/tgbaalgos/emptinesscheck.hh: New files.
 
 2003-09-22  Alexandre Duret-Lutz  <aduret@src.lip6.fr>
 
diff --git a/src/misc/bddlt.hh b/src/misc/bddlt.hh
index 2ca90a9c6..cdbbc4077 100644
--- a/src/misc/bddlt.hh
+++ b/src/misc/bddlt.hh
@@ -2,11 +2,13 @@
 # define SPOT_MISC_BDDLT_HH
 
 # include <bdd.h>
+# include <functional>
 
 namespace spot
 {
   /// Comparison functor for BDDs.
-  struct bdd_less_than
+  struct bdd_less_than :
+    public std::binary_function<const bdd&, const bdd&, bool>
   {
     bool
     operator()(const bdd& left, const bdd& right) const
diff --git a/src/misc/hash.hh b/src/misc/hash.hh
index 379707b21..2bf60acbb 100644
--- a/src/misc/hash.hh
+++ b/src/misc/hash.hh
@@ -2,6 +2,7 @@
 #  define SPOT_MISC_HASH_HH
 
 #  include <string>
+#  include <functional>
 
 // See the G++ FAQ for details about the following.
 #  ifdef __GNUC__
@@ -34,7 +35,8 @@ namespace spot
 
   /// A hash function for pointers.
   template <class T>
-  struct ptr_hash
+  struct ptr_hash :
+    public std::unary_function<const T*, size_t>
   {
     size_t operator()(const T* p) const
     {
@@ -43,7 +45,9 @@ namespace spot
   };
 
   /// A hash function for strings.
-  struct string_hash : Sgi::hash<const char*>
+  struct string_hash :
+    public Sgi::hash<const char*>,
+    public std::unary_function<const std::string&, size_t>
   {
     size_t operator()(const std::string& s) const
     {
diff --git a/src/tgba/state.hh b/src/tgba/state.hh
index 3a3d91f92..df98641f1 100644
--- a/src/tgba/state.hh
+++ b/src/tgba/state.hh
@@ -4,6 +4,7 @@
 #include <cstddef>
 #include <bdd.h>
 #include <cassert>
+#include <functional>
 
 namespace spot
 {
@@ -64,7 +65,8 @@ namespace spot
   ///   // Remember how many times each state has been visited.
   ///   std::map<spot::state*, int, spot::state_ptr_less_than> seen;
   /// \endcode
-  struct state_ptr_less_than
+  struct state_ptr_less_than :
+    public std::binary_function<const state*, const state*, bool>
   {
     bool
     operator()(const state* left, const state* right) const
@@ -86,7 +88,8 @@ namespace spot
   ///   Sgi::hash_map<spot::state*, int, spot::state_ptr_less_than,
   ///                                    spot::state_ptr_equal> seen;
   /// \endcode
-  struct state_ptr_equal
+  struct state_ptr_equal :
+    public std::binary_function<const state*, const state*, bool>
   {
     bool
     operator()(const state* left, const state* right) const
@@ -108,7 +111,8 @@ namespace spot
   ///   Sgi::hash_map<spot::state*, int, spot::state_ptr_less_than,
   ///                                    spot::state_ptr_equal> seen;
   /// \endcode
-  struct state_ptr_hash
+  struct state_ptr_hash :
+    public std::unary_function<const state*, size_t>
   {
     size_t
     operator()(const state* that) const
diff --git a/src/tgbaalgos/lbtt.cc b/src/tgbaalgos/lbtt.cc
index b060d5d73..5032f543c 100644
--- a/src/tgbaalgos/lbtt.cc
+++ b/src/tgbaalgos/lbtt.cc
@@ -3,6 +3,7 @@
 #include <set>
 #include <string>
 #include <sstream>
+#include <functional>
 #include "tgba/tgba.hh"
 #include "save.hh"
 #include "tgba/bddprint.hh"
@@ -87,7 +88,9 @@ namespace spot
 
   typedef std::pair<state*, bdd> state_acc_pair;
 
-  struct state_acc_pair_equal
+  struct state_acc_pair_equal :
+    public std::binary_function<const state_acc_pair&,
+                                const state_acc_pair&, bool>
   {
     bool
     operator()(const state_acc_pair& left, const state_acc_pair& right) const
@@ -98,7 +101,8 @@ namespace spot
     }
   };
 
-  struct state_acc_pair_hash
+  struct state_acc_pair_hash :
+    public std::unary_function<const state_acc_pair&, size_t>
   {
     bool
     operator()(const state_acc_pair& that) const