diff --git a/CHANGES b/CHANGES
index 3ed37883a89a1e64bad33ceedaa5b41577034397..da019780291f43841873c11f0d44298d6c16abe7 100644
--- a/CHANGES
+++ b/CHANGES
@@ -6,6 +6,11 @@
 
                                   Changelog
 
+Yang Tse (18 Aug 2008)
+- Added test case 557 to verify libcurl's internal curl_m*printf() functions
+  formatting functionality when handling signed and unsigned longs, as well as
+  our curl_off_t data type.
+
 Yang Tse (17 Aug 2008)
 - OpenSSl enabled NetWare builds are changed to use the 'openssl' subdirectory
   when including the OpenSSL header files. This is the recommended setting, this
diff --git a/tests/data/Makefile.am b/tests/data/Makefile.am
index d8dbbb23c24954eaa2c0dacc5dc357fdd56dd0c8..b51de8e524056afacaeaea7683c8914664c9e21a 100644
--- a/tests/data/Makefile.am
+++ b/tests/data/Makefile.am
@@ -51,7 +51,7 @@ EXTRA_DIST = test1 test108 test117 test127 test20 test27 test34 test46	   \
  test1021 test1022 test1023 test309 test616 test617 test618 test619        \
  test620 test621 test622 test623 test624 test625 test626 test627 test554   \
  test1024 test1025 test555 test1026 test1027 test1028 test1029 test1030    \
- test556 test1031 test628 test629 test630 test631 test632 test1032         \
+ test556 test557 test1031 test628 test629 test630 test631 test632 test1032 \
  test1033 test539 test1034 test1035 test1036 test1037 test1038 test1039    \
  test1040 test1041 test1042 test1043 test1044 test1045 test1046 test1047   \
  test1048 test1049 test1050 test1051 test1052 test1053 test1054 test1055   \
diff --git a/tests/data/test557 b/tests/data/test557
new file mode 100644
index 0000000000000000000000000000000000000000..2f1c1435a30e31b6b202363e4ccb489766500a55
--- /dev/null
+++ b/tests/data/test557
@@ -0,0 +1,52 @@
+<testcase>
+<info>
+<keywords>
+curl_mprintf
+</keywords>
+</info>
+# Server-side
+
+<reply>
+</reply>
+
+# Client-side
+<client>
+<server>
+none
+</server>
+<tool>
+lib557
+</tool>
+ <name>
+curl_mprintf
+ </name>
+ <command>
+nothing
+</command>
+</client>
+
+#
+# Verify data after the test has been "shot"
+<verify>
+<stdout mode="text">
+unsigned long test #1: OK
+unsigned long test #2: OK
+unsigned long test #3: OK
+unsigned long test #4: OK
+signed long test #1: OK
+signed long test #2: OK
+signed long test #3: OK
+signed long test #4: OK
+signed long test #5: OK
+signed long test #6: OK
+signed long test #7: OK
+curl_off_t test #1: OK
+curl_off_t test #2: OK
+curl_off_t test #3: OK
+curl_off_t test #4: OK
+curl_off_t test #5: OK
+curl_off_t test #6: OK
+curl_off_t test #7: OK
+</stdout>
+</verify>
+</testcase>
diff --git a/tests/libtest/Makefile.am b/tests/libtest/Makefile.am
index b24b90014df1a6a210daf05407aa177e27611f53..94774c310cd9d109203db4a78500b062b88bb914 100644
--- a/tests/libtest/Makefile.am
+++ b/tests/libtest/Makefile.am
@@ -53,7 +53,7 @@ noinst_PROGRAMS = lib500 lib501 lib502 lib503 lib504 lib505 lib506	\
   lib517 lib518 lib519 lib520 lib521 lib523 lib524 lib525 lib526 lib527	\
   lib529 lib530 lib532 lib533 lib536 lib537 lib540 lib541 lib542 lib543 \
   lib544 lib545 lib547 lib548 lib549 lib552 lib553 lib554 lib555 lib556 \
-  lib539
+  lib539 lib557
 
 # Dependencies (may need to be overriden)
 LDADD = $(LIBDIR)/libcurl.la
@@ -160,3 +160,5 @@ lib553_SOURCES = lib553.c $(SUPPORTFILES)
 lib554_SOURCES = lib554.c $(SUPPORTFILES)
 
 lib556_SOURCES = lib556.c $(SUPPORTFILES)
+
+lib557_SOURCES = lib557.c $(SUPPORTFILES)
diff --git a/tests/libtest/lib557.c b/tests/libtest/lib557.c
new file mode 100644
index 0000000000000000000000000000000000000000..8e49dbff3a1a3d57b2d786c7565925fe264cb052
--- /dev/null
+++ b/tests/libtest/lib557.c
@@ -0,0 +1,269 @@
+/*****************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * $Id$
+ */
+
+/*
+ * The purpose of this test is to minimally exercise libcurl's internal
+ * curl_m*printf formatting capabilities and handling of some data types.
+ */
+
+#include "test.h"
+
+int curl_msprintf(char *buffer, const char *format, ...);
+
+
+#if (CURL_SIZEOF_CURL_OFF_T > 4)
+#  if (CURL_SIZEOF_LONG > 4)
+#    define MPRNT_SUFFIX_CURL_OFF_T  L
+#  else
+#    define MPRNT_SUFFIX_CURL_OFF_T  LL
+#  endif
+#else
+#  if (CURL_SIZEOF_LONG > 2)
+#    define MPRNT_SUFFIX_CURL_OFF_T  L
+#  else
+#    define MPRNT_SUFFIX_CURL_OFF_T  LL
+#  endif
+#endif
+
+#ifdef CURL_ISOCPP
+#  define MPRNT_OFF_T_C_HELPER2(Val,Suffix) Val ## Suffix
+#else
+#  define MPRNT_OFF_T_C_HELPER2(Val,Suffix) Val/**/Suffix
+#endif
+#define MPRNT_OFF_T_C_HELPER1(Val,Suffix) MPRNT_OFF_T_C_HELPER2(Val,Suffix)
+#define MPRNT_OFF_T_C(Val)  MPRNT_OFF_T_C_HELPER1(Val,MPRNT_SUFFIX_CURL_OFF_T)
+
+
+#define BUFSZ    256
+#define NUM_ULONG_TESTS  4
+#define NUM_SLONG_TESTS  7
+#define NUM_COFFT_TESTS  7
+
+
+struct unslong_st {
+  unsigned long num;    /* unsigned long   */
+  const char *expected; /* expected string */
+  char result[BUFSZ];   /* result string   */
+};
+
+
+struct siglong_st {
+  long num;             /* signed long     */
+  const char *expected; /* expected string */
+  char result[BUFSZ];   /* result string   */
+};
+
+
+struct curloff_st {
+  curl_off_t num;       /* curl_off_t      */
+  const char *expected; /* expected string */
+  char result[BUFSZ];   /* result string   */
+};
+
+
+static struct unslong_st ul_test[NUM_ULONG_TESTS];
+static struct siglong_st sl_test[NUM_SLONG_TESTS];
+static struct curloff_st co_test[NUM_COFFT_TESTS];
+
+
+static int test_unsigned_long_formatting(void)
+{
+  int i, j;
+  int failed = 0;
+
+  ul_test[0].num = 0x0L;
+  ul_test[0].expected = "0";
+  ul_test[1].num = 0x1L;
+  ul_test[1].expected = "1";
+#if (CURL_SIZEOF_LONG == 2)
+  ul_test[2].num = 0xFFL;
+  ul_test[2].expected = "255";
+  ul_test[3].num = 0xFFFFL;
+  ul_test[3].expected = "65535";
+#elif (CURL_SIZEOF_LONG == 4)
+  ul_test[2].num = 0xFFFFL;
+  ul_test[2].expected = "65535";
+  ul_test[3].num = 0xFFFFFFFFL;
+  ul_test[3].expected = "4294967295";
+#elif (CURL_SIZEOF_LONG == 8)
+  ul_test[2].num = 0xFFFFFFFFL;
+  ul_test[2].expected = "4294967295";
+  ul_test[3].num = 0xFFFFFFFFFFFFFFFFL;
+  ul_test[3].expected = "18446744073709551615";
+#endif
+
+  for(i=0; i<NUM_ULONG_TESTS; i++) {
+
+    for(j=0; j<BUFSZ; j++)
+      ul_test[i].result[j] = 'X';
+    ul_test[i].result[BUFSZ-1] = '\0';
+
+    (void)curl_msprintf(ul_test[i].result, "%lu", ul_test[i].num);
+
+    if(!memcmp(ul_test[i].result,
+               ul_test[i].expected,
+               strlen(ul_test[i].expected)))
+      printf("unsigned long test #%d: OK\n", i+1);
+    else {
+      printf("unsigned long test #%d: Failed (Expected: %s Got: %s)\n",
+             i+1, ul_test[i].expected, ul_test[i].result);
+      failed++;
+    }
+
+  }
+
+  return failed;
+}
+
+
+static int test_signed_long_formatting(void)
+{
+  int i, j;
+  int failed = 0;
+
+  sl_test[0].num = 0x0L;
+  sl_test[0].expected = "0";
+  sl_test[1].num = 0x1L;
+  sl_test[1].expected = "1";
+  sl_test[2].num = -0x1L;
+  sl_test[2].expected = "-1";
+#if (CURL_SIZEOF_LONG == 2)
+  sl_test[3].num = 0x7FL;
+  sl_test[3].expected = "127";
+  sl_test[4].num = 0x7FFFL;
+  sl_test[4].expected = "32767";
+  sl_test[5].num = -0x7FL -1L;
+  sl_test[5].expected = "-128";
+  sl_test[6].num = -0x7FFFL -1L;
+  sl_test[6].expected = "-32768";
+#elif (CURL_SIZEOF_LONG == 4)
+  sl_test[3].num = 0x7FFFL;
+  sl_test[3].expected = "32767";
+  sl_test[4].num = 0x7FFFFFFFL;
+  sl_test[4].expected = "2147483647";
+  sl_test[5].num = -0x7FFFL -1L;
+  sl_test[5].expected = "-32768";
+  sl_test[6].num = -0x7FFFFFFFL -1L;
+  sl_test[6].expected = "-2147483648";
+#elif (CURL_SIZEOF_LONG == 8)
+  sl_test[3].num = 0x7FFFFFFFL;
+  sl_test[3].expected = "2147483647";
+  sl_test[4].num = 0x7FFFFFFFFFFFFFFFL;
+  sl_test[4].expected = "9223372036854775807";
+  sl_test[5].num = -0x7FFFFFFFL -1L;
+  sl_test[5].expected = "-2147483648";
+  sl_test[6].num = -0x7FFFFFFFFFFFFFFFL -1L;
+  sl_test[6].expected = "-9223372036854775808";
+#endif
+
+  for(i=0; i<NUM_SLONG_TESTS; i++) {
+
+    for(j=0; j<BUFSZ; j++)
+      sl_test[i].result[j] = 'X';
+    sl_test[i].result[BUFSZ-1] = '\0';
+
+    (void)curl_msprintf(sl_test[i].result, "%ld", sl_test[i].num);
+
+    if(!memcmp(sl_test[i].result,
+               sl_test[i].expected,
+               strlen(sl_test[i].expected)))
+      printf("signed long test #%d: OK\n", i+1);
+    else {
+      printf("signed long test #%d: Failed (Expected: %s Got: %s)\n",
+             i+1, sl_test[i].expected, sl_test[i].result);
+      failed++;
+    }
+
+  }
+
+  return failed;
+}
+
+
+static int test_curl_off_t_formatting(void)
+{
+  int i, j;
+  int failed = 0;
+
+  co_test[0].num = MPRNT_OFF_T_C(0x0);
+  co_test[0].expected = "0";
+  co_test[1].num = MPRNT_OFF_T_C(0x1);
+  co_test[1].expected = "1";
+  co_test[2].num = -MPRNT_OFF_T_C(0x1);
+  co_test[2].expected = "-1";
+#if (CURL_SIZEOF_CURL_OFF_T == 2)
+  co_test[3].num = MPRNT_OFF_T_C(0x7F);
+  co_test[3].expected = "127";
+  co_test[4].num = MPRNT_OFF_T_C(0x7FFF);
+  co_test[4].expected = "32767";
+  co_test[5].num = -MPRNT_OFF_T_C(0x7F) -MPRNT_OFF_T_C(1);
+  co_test[5].expected = "-128";
+  co_test[6].num = -MPRNT_OFF_T_C(0x7FFF) -MPRNT_OFF_T_C(1);
+  co_test[6].expected = "-32768";
+#elif (CURL_SIZEOF_CURL_OFF_T == 4)
+  co_test[3].num = MPRNT_OFF_T_C(0x7FFF);
+  co_test[3].expected = "32767";
+  co_test[4].num = MPRNT_OFF_T_C(0x7FFFFFFF);
+  co_test[4].expected = "2147483647";
+  co_test[5].num = -MPRNT_OFF_T_C(0x7FFF) -MPRNT_OFF_T_C(1);
+  co_test[5].expected = "-32768";
+  co_test[6].num = -MPRNT_OFF_T_C(0x7FFFFFFF) -MPRNT_OFF_T_C(1);
+  co_test[6].expected = "-2147483648";
+#elif (CURL_SIZEOF_CURL_OFF_T == 8)
+  co_test[3].num = MPRNT_OFF_T_C(0x7FFFFFFF);
+  co_test[3].expected = "2147483647";
+  co_test[4].num = MPRNT_OFF_T_C(0x7FFFFFFFFFFFFFFF);
+  co_test[4].expected = "9223372036854775807";
+  co_test[5].num = -MPRNT_OFF_T_C(0x7FFFFFFF) -MPRNT_OFF_T_C(1);
+  co_test[5].expected = "-2147483648";
+  co_test[6].num = -MPRNT_OFF_T_C(0x7FFFFFFFFFFFFFFF) -MPRNT_OFF_T_C(1);
+  co_test[6].expected = "-9223372036854775808";
+#endif
+
+  for(i=0; i<NUM_COFFT_TESTS; i++) {
+
+    for(j=0; j<BUFSZ; j++)
+      co_test[i].result[j] = 'X';
+    co_test[i].result[BUFSZ-1] = '\0';
+
+    (void)curl_msprintf(co_test[i].result, "%" FORMAT_OFF_T, co_test[i].num);
+
+    if(!memcmp(co_test[i].result,
+               co_test[i].expected,
+               strlen(co_test[i].expected)))
+      printf("curl_off_t test #%d: OK\n", i+1);
+    else {
+      printf("curl_off_t test #%d: Failed (Expected: %s Got: %s)\n",
+             i+1, co_test[i].expected, co_test[i].result);
+      failed++;
+    }
+
+  }
+
+  return failed;
+}
+
+
+int test(char *URL)
+{
+  int errors = 0;
+  (void)URL; /* not used */
+
+  errors += test_unsigned_long_formatting();
+
+  errors += test_signed_long_formatting();
+
+  errors += test_curl_off_t_formatting();
+
+  if(errors)
+    return TEST_ERR_MAJOR_BAD;
+  else
+    return 0;
+}