diff --git a/ChangeLog b/ChangeLog
index c3fe925de..583dabc94 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2003-10-15  Alexandre Duret-Lutz  <adl@src.lip6.fr>
+
+	* iface/gspn/ltlgspn.cc (main): Allow invocations with
+	only one atomic proposition.
+
 2003-10-14  Alexandre Duret-Lutz  <adl@src.lip6.fr>
 
 	* src/misc/bddalloc.cc (bdd_allocator::initialize): Augment
diff --git a/iface/gspn/ltlgspn.cc b/iface/gspn/ltlgspn.cc
index 1f66fdc46..7882f3bde 100644
--- a/iface/gspn/ltlgspn.cc
+++ b/iface/gspn/ltlgspn.cc
@@ -66,7 +66,7 @@ main(int argc, char **argv)
 	    }
 	  ++formula_index;
 	}
-      if (argc < formula_index + 4)
+      if (argc < formula_index + 3)
 	syntax(argv[0]);