diff --git a/ChangeLog b/ChangeLog
index 82587bc36d..009fa06023 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri May 14 07:27:07 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* marshal.c (w_float): strip ".0" from end for rubyspec.
+
 Fri May 14 01:17:10 2010  Yusuke Endoh  <mame@tsg.ne.jp>
 
 	* vm_core.c (rb_thread_struct): add a field for sigaltstack.
diff --git a/marshal.c b/marshal.c
index 857dd7361c..edcb9556cb 100644
--- a/marshal.c
+++ b/marshal.c
@@ -369,7 +369,10 @@ w_float(double d, struct dump_arg *arg)
 	else           w_cstr("0", arg);
     }
     else {
-	w_bytes(buf, ruby_dbl2cstr(d, buf, (int)sizeof(buf)), arg);
+	int len = ruby_dbl2cstr(d, buf, (int)sizeof(buf));
+	if (len > 2 && buf[len - 1] == '0' && buf[len - 2] == '.')
+	    len -= 2;
+	w_bytes(buf, len, arg);
     }
 }