diff --git a/ChangeLog b/ChangeLog
index a1b010e85..77a5f9055 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2003-09-04  David Shaw  <dshaw@jabberwocky.com>
+
+	* configure.ac: Drop TIGER/192 support.  Check for UINT64_C to go
+	along with uint64_t.
+
 2003-09-01  David Shaw  <dshaw@jabberwocky.com>
 
 	* NEWS: Note --list-options, --verify-options, the deprecation of
diff --git a/configure.ac b/configure.ac
index c8fe36a6c..c37c61aa2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -113,8 +113,6 @@ use_cast5=yes
 use_blowfish=yes
 use_aes=yes
 use_twofish=yes
-use_tiger192=no
-use_old_tiger192=no
 use_sha256=yes
 use_sha512=yes
 use_exec=yes
@@ -193,34 +191,6 @@ if test x"$use_twofish" = xyes ; then
    AC_DEFINE(USE_TWOFISH,1,[Define to include the TWOFISH cipher])
 fi
 
-dnl this is because the stable branch calls it just "tiger".
-AC_ARG_ENABLE(tiger,,use_tiger192=$enableval)
-AC_ARG_ENABLE(old-tiger,,use_old_tiger192=$enableval)
-
-dnl TIGER192 is actually defined only after we confirm 64-bit support
-dnl later
-AC_MSG_CHECKING([whether to enable the nonstandard TIGER/192 digest])
-AC_ARG_ENABLE(tiger192,
-   AC_HELP_STRING([--enable-tiger192],[enable the nonstandard TIGER/192 digest]),
-   use_tiger192=$enableval)
-AC_MSG_RESULT($use_tiger192)
-
-AC_MSG_CHECKING([whether to enable old-style nonstandard TIGER/192 digest support])
-AC_ARG_ENABLE(old-tiger192,
-   AC_HELP_STRING([--enable-old-tiger192],[enable old-style nonstandard TIGER/192 digest support]),
-   use_old_tiger=$enableval)
-AC_MSG_RESULT($use_old_tiger192)
-
-if test x"$use_tiger192" = xyes || test x"$use_old_tiger192" = xyes ; then
-   AC_MSG_WARN([[
-***
-*** The TIGER/192 digest is in the process of being removed from the
-*** OpenPGP standard.  While it hasn't been removed from GnuPG yet, it
-*** will be removed in a future version.  For the sake of future
-*** compatibility, please do not use this digest.
-***]])
-fi
-
 AC_MSG_CHECKING([whether to enable the SHA-256 digest])
 AC_ARG_ENABLE(sha256,
    AC_HELP_STRING([--disable-sha256],[disable the SHA-256 digest]),
@@ -692,7 +662,15 @@ AC_CHECK_SIZEOF(unsigned short)
 AC_CHECK_SIZEOF(unsigned int)
 AC_CHECK_SIZEOF(unsigned long)
 AC_CHECK_SIZEOF(unsigned long long)
-AC_CHECK_SIZEOF(uint64_t)
+
+# Ensure that we have UINT64_C before we bother to check for uint64_t
+AC_CACHE_CHECK([for UINT64_C],[gnupg_cv_uint64_c_works],
+   AC_COMPILE_IFELSE(AC_LANG_PROGRAM([#include <inttypes.h>
+uint64_t foo=UINT64_C(42);]),gnupg_cv_uint64_c_works=yes,gnupg_cv_uint64_c_works=no))
+
+if test "$gnupg_cv_uint64_c_works" = "yes" ; then
+   AC_CHECK_SIZEOF(uint64_t)
+fi
 
 if test "$ac_cv_sizeof_unsigned_short" = "0" \
    || test "$ac_cv_sizeof_unsigned_int" = "0" \
@@ -704,20 +682,9 @@ dnl Do we have any 64-bit data types?
 if test "$ac_cv_sizeof_unsigned_int" != "8" \
    && test "$ac_cv_sizeof_unsigned_long" != "8" \
    && test "$ac_cv_sizeof_unsigned_long_long" != "8" \
-   && test "$ac_cv_sizeof_uint64_t" != "8"; then
-    AC_MSG_WARN([No 64-bit types.  Disabling TIGER/192, SHA-384, and SHA-512])
+   && test x"$ac_cv_sizeof_uint64_t" != "x8"; then
+    AC_MSG_WARN([No 64-bit types.  Disabling SHA-384 and SHA-512])
 else
-  if test x"$use_tiger192" = xyes ; then
-     AC_SUBST(TIGER_O,tiger.o)
-     AC_DEFINE(USE_TIGER192,1,[Define to include the TIGER/192 digest])
-  fi
-
-  if test "$use_old_tiger192" = yes ; then
-     AC_SUBST(TIGER_O,tiger.o)
-     AC_DEFINE(USE_TIGER192,1,[Define to include the TIGER/192 digest])
-     AC_DEFINE(USE_OLD_TIGER,1,[Define to use the old fake OID for TIGER/192 digest support])
-  fi
-
   if test x"$use_sha512" = xyes ; then
      AC_SUBST(SHA512_O,sha512.o)
      AC_DEFINE(USE_SHA512,1,[Define to include the SHA-384 and SHA-512 digests])