diff --git a/ChangeLog b/ChangeLog
index 6b285c01dd2b59..3138fb64ba3df5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Mar 21 17:04:30 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* bignum.c (rb_big2str0): round up for the most significant digit.
+	  [ruby-core:10686]
+
 Tue Mar 21 08:20:00 2007  Nathaniel Talbott  <ntalbott@ruby-lang.org>
 
 	* test/testunit/collector/test_dir.rb: Fixed test/unit tests that 
diff --git a/bignum.c b/bignum.c
index f0c3a0f63ae32f..aec25c13d96e12 100644
--- a/bignum.c
+++ b/bignum.c
@@ -601,10 +601,10 @@ rb_big2str0(VALUE x, int base, int trim)
 	j = j * 53L / 84 + 1;
 	break;
       case 4: case 5: case 6: case 7:
-	j /= 2;
+	j = (j + 1) / 2;
 	break;
       case 8: case 9:
-	j /= 3;
+	j = (j + 2) / 3;
 	break;
       case 10: case 11: case 12: case 13: case 14: case 15:
 	j = j * 28L / 93 + 1;
@@ -612,10 +612,10 @@ rb_big2str0(VALUE x, int base, int trim)
       case 16: case 17: case 18: case 19: case 20: case 21:
       case 22: case 23: case 24: case 25: case 26: case 27:
       case 28: case 29: case 30: case 31:
-	j /= 4;
+	j = (j + 3) / 4;
 	break;
       case 32: case 33: case 34: case 35: case 36:
-	j /= 5;
+	j = (j + 4) / 5;
 	break;
       default:
 	rb_raise(rb_eArgError, "illegal radix %d", base);
diff --git a/version.h b/version.h
index 3a23002b201f6c..962b751f6a4a7f 100644
--- a/version.h
+++ b/version.h
@@ -1,7 +1,7 @@
 #define RUBY_VERSION "1.9.0"
-#define RUBY_RELEASE_DATE "2007-03-20"
+#define RUBY_RELEASE_DATE "2007-03-21"
 #define RUBY_VERSION_CODE 190
-#define RUBY_RELEASE_CODE 20070320
+#define RUBY_RELEASE_CODE 20070321
 #define RUBY_PATCHLEVEL 0
 
 #define RUBY_VERSION_MAJOR 1
@@ -9,7 +9,7 @@
 #define RUBY_VERSION_TEENY 0
 #define RUBY_RELEASE_YEAR 2007
 #define RUBY_RELEASE_MONTH 3
-#define RUBY_RELEASE_DAY 20
+#define RUBY_RELEASE_DAY 21
 
 RUBY_EXTERN const char ruby_version[];
 RUBY_EXTERN const char ruby_release_date[];