diff --git a/ChangeLog b/ChangeLog
index b755dd760e..8f8a0066b1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Nov 28 09:51:42 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* bignum.c (rb_big2str0): do not clobber space for sign.
+
+	* sprintf.c (remove_sign_bits): extends sign bit first.
+
 Wed Nov 21 01:04:12 2007  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* object.c (nil_plus): remove unused function.  [ruby-core:13737]
diff --git a/bignum.c b/bignum.c
index e6ecb3933b..2fd7624110 100644
--- a/bignum.c
+++ b/bignum.c
@@ -709,7 +709,7 @@ rb_big2str0(x, base, trim)
 	while (k--) {
 	    s[--j] = ruby_digitmap[num % base];
 	    num /= base;
-	    if (!trim && j < 1) break;
+	    if (!trim && j <= 1) break;
 	    if (trim && i == 0 && num == 0) break;
 	}
     }
diff --git a/sprintf.c b/sprintf.c
index de997098ba..e32c456b63 100644
--- a/sprintf.c
+++ b/sprintf.c
@@ -18,6 +18,8 @@
 #include <math.h>
 
 #define BIT_DIGITS(N)   (((N)*146)/485 + 1)  /* log2(10) =~ 146/485 */
+#define BITSPERDIG (SIZEOF_BDIGITS*CHAR_BIT)
+#define EXTENDSIGN(n, l) (((~0 << (n)) >> (((n)*(l)) % BITSPERDIG)) & ~(~0 << (n)))
 
 static void fmt_setup _((char*,int,int,int,int));
 
@@ -36,7 +38,7 @@ remove_sign_bits(str, base)
 	}
     }
     else if (base == 8) {
-	if (*t == '3') t++;
+	*t |= EXTENDSIGN(3, strlen(t));
 	while (*t == '7') {
 	    t++;
 	}
diff --git a/version.h b/version.h
index 234e6244fb..f2b83e471f 100644
--- a/version.h
+++ b/version.h
@@ -1,7 +1,7 @@
 #define RUBY_VERSION "1.8.6"
-#define RUBY_RELEASE_DATE "2007-11-21"
+#define RUBY_RELEASE_DATE "2007-11-28"
 #define RUBY_VERSION_CODE 186
-#define RUBY_RELEASE_CODE 20071121
+#define RUBY_RELEASE_CODE 20071128
 #define RUBY_PATCHLEVEL 5000
 
 #define RUBY_VERSION_MAJOR 1
@@ -9,7 +9,7 @@
 #define RUBY_VERSION_TEENY 6
 #define RUBY_RELEASE_YEAR 2007
 #define RUBY_RELEASE_MONTH 11
-#define RUBY_RELEASE_DAY 21
+#define RUBY_RELEASE_DAY 28
 
 #ifdef RUBY_EXTERN
 RUBY_EXTERN const char ruby_version[];