diff --git a/ChangeLog b/ChangeLog
index 3a716c7..b681024 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2004-10-20  Richard B. Kreckel  <kreckel@ginac.de>
+
+	* include/cln/types.h: Use 64 bit digits on x86_64 CPU.
+
 2004-10-12  Richard B. Kreckel  <kreckel@ginac.de>
 
 	* src/integer/conv/cl_I_from_digits.cc (digits_to_I): Speedup when
diff --git a/include/cln/types.h b/include/cln/types.h
index 5075723..efe3242 100644
--- a/include/cln/types.h
+++ b/include/cln/types.h
@@ -119,7 +119,7 @@
     typedef int sintD;
     typedef unsigned int uintD;
   #else  // we are not using GMP, so just guess something reasonable
-    #if (defined(HAVE_FAST_LONGLONG) && (defined(__alpha__) || defined(__ia64__)))
+    #if (defined(HAVE_FAST_LONGLONG) && (defined(__alpha__) || defined(__ia64__) || defined(__x86_64__)))
       #define intDsize 64
       typedef sint64  sintD;
       typedef uint64  uintD;