diff --git a/Packages/Number_types/changes.txt b/Packages/Number_types/changes.txt
index b3b93764c86..7c7ba0451cb 100644
--- a/Packages/Number_types/changes.txt
+++ b/Packages/Number_types/changes.txt
@@ -1,3 +1,6 @@
+4.121 (27 October 2003)
+- Fix Gmpq's operator>> in case of end of stream.
+
 4.120 (22 October 2003) [af]
 - new headers
 
diff --git a/Packages/Number_types/include/CGAL/Gmpq.h b/Packages/Number_types/include/CGAL/Gmpq.h
index 1934252fb5e..45c90930160 100644
--- a/Packages/Number_types/include/CGAL/Gmpq.h
+++ b/Packages/Number_types/include/CGAL/Gmpq.h
@@ -466,10 +466,11 @@ operator>>(std::istream& is, Gmpq &z)
   Gmpz n, d;
   is >> n;
   is >> c;
-  CGAL_assertion(c == '/');
+  CGAL_assertion(!is || c == '/');
   is >> d;
-  z = Gmpq(n,d);
-  
+  if (is)
+    z = Gmpq(n,d);
+
   return is;
 }