diff --git a/ase/config.h.in b/ase/config.h.in
index ab1c6101..e09be041 100644
--- a/ase/config.h.in
+++ b/ase/config.h.in
@@ -14,22 +14,22 @@
 #undef XP_HAVE_LONG_DOUBLE
 
 /* sizeof (char) */
-#define SIZEOF_CHAR 1
+#define SIZEOF_CHAR 0
 
 /* sizeof (short) */
-#define SIZEOF_SHORT 1
+#define SIZEOF_SHORT 0
 
 /* sizeof (int) */
-#define SIZEOF_INT  1
+#define SIZEOF_INT  0
 
 /* sizeof (long) */
-#define SIZEOF_LONG 1
+#define SIZEOF_LONG 0
 
 /* sizeof (long long) */
-#define SIZEOF_LONG_LONG  1
+#define SIZEOF_LONG_LONG  0
 
 /* sizeof (void*) */
-#define SIZEOF_VOID_P  1
+#define SIZEOF_VOID_P  0
 
 /* fcntl.h */
 #undef XP_HAVE_FCNTL_H
diff --git a/ase/configure.ac b/ase/configure.ac
index e6b4db0f..cbb38ff5 100644
--- a/ase/configure.ac
+++ b/ase/configure.ac
@@ -1,6 +1,6 @@
 AC_PREREQ(2.53)
 AC_INIT([xpkit], [deb-0.1.0])
-AC_REVISION([$Revision: 1.17 $])
+AC_REVISION([$Revision: 1.18 $])
 AC_CONFIG_HEADER([xp/config.h])
 
 # Checks for programs.
@@ -28,12 +28,17 @@ AC_C_BIGENDIAN(
 # Checks for data types
 AC_CHECK_TYPE(long long, [AC_DEFINE([XP_HAVE_LONG_LONG],[],[long long])])
 AC_CHECK_TYPE(long double, [AC_DEFINE([XP_HAVE_LONG_DOUBLE],[],[long double])])
+AC_CHECK_TYPE(__int64, [AC_DEFINE([XP_HAVE_INT64],[],[__int64])])
 
 AC_CHECK_SIZEOF(char)
 AC_CHECK_SIZEOF(short)
 AC_CHECK_SIZEOF(int)
 AC_CHECK_SIZEOF(long)
 AC_CHECK_SIZEOF(long long)
+AC_CHECK_SIZEOF(__int64)
+AC_CHECK_SIZEOF(float)
+AC_CHECK_SIZEOF(double)
+AC_CHECK_SIZEOF(long double)
 AC_CHECK_SIZEOF(void *)
 
 # Checks for library functions.