diff --git a/ChangeLog b/ChangeLog
index 0a54e6b66d..ab2e2af3f9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue May 13 07:56:36 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* string.c (rb_str_cat): fixed buffer overrun reported by
+	  Christopher Thompson <cthompson at nexopia.com> in [ruby-core:16746]
+
 Mon May 12 13:57:19 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* eval.c (is_defined): add NODE_OP_ASGN_{OR,AND}.  "defined?(a||=1)"
diff --git a/string.c b/string.c
index d868df7faf..0f584aa25d 100644
--- a/string.c
+++ b/string.c
@@ -761,7 +761,7 @@ rb_str_cat(str, ptr, len)
     }
     if (FL_TEST(str, STR_ASSOC)) {
 	rb_str_modify(str);
-	REALLOC_N(RSTRING(str)->ptr, char, RSTRING(str)->len+len);
+	REALLOC_N(RSTRING(str)->ptr, char, RSTRING(str)->len+len+1);
 	memcpy(RSTRING(str)->ptr + RSTRING(str)->len, ptr, len);
 	RSTRING(str)->len += len;
 	RSTRING(str)->ptr[RSTRING(str)->len] = '\0'; /* sentinel */
diff --git a/version.h b/version.h
index d810961b2b..0925987762 100644
--- a/version.h
+++ b/version.h
@@ -1,7 +1,7 @@
 #define RUBY_VERSION "1.8.7"
-#define RUBY_RELEASE_DATE "2008-05-12"
+#define RUBY_RELEASE_DATE "2008-05-13"
 #define RUBY_VERSION_CODE 187
-#define RUBY_RELEASE_CODE 20080512
+#define RUBY_RELEASE_CODE 20080513
 #define RUBY_PATCHLEVEL 5000
 
 #define RUBY_VERSION_MAJOR 1
@@ -9,7 +9,7 @@
 #define RUBY_VERSION_TEENY 7
 #define RUBY_RELEASE_YEAR 2008
 #define RUBY_RELEASE_MONTH 5
-#define RUBY_RELEASE_DAY 12
+#define RUBY_RELEASE_DAY 13
 
 #ifdef RUBY_EXTERN
 RUBY_EXTERN const char ruby_version[];