diff --git a/ChangeLog b/ChangeLog
index 4003a6ad4b..7ef4616fe6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Tue Jul 22 02:22:45 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* string.c (rb_str_equal): should return nil for non string
+	  operand to conform comparable convention. [ruby-dev:20759]
+
+	* object.c (rb_equal): preserve nil if "==" returns nil.
+
 Tue Jul 22 00:19:19 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* lib/tmpdir.rb: new library to get temporary directory path,
diff --git a/object.c b/object.c
index 7e8b5e68e1..e168fa7505 100644
--- a/object.c
+++ b/object.c
@@ -42,7 +42,7 @@ rb_equal(obj1, obj2)
     if (obj1 == obj2) return Qtrue;
     result = rb_funcall(obj1, id_eq, 1, obj2);
     if (RTEST(result)) return Qtrue;
-    return Qfalse;
+    return result;
 }
 
 int
diff --git a/string.c b/string.c
index fc1e66cb26..c7b5ddd9f2 100644
--- a/string.c
+++ b/string.c
@@ -792,7 +792,7 @@ rb_str_equal(str1, str2)
     if (str1 == str2) return Qtrue;
     if (TYPE(str2) != T_STRING) {
 	if (!rb_respond_to(str2, rb_intern("to_str"))) {
-	    return Qfalse;
+	    return Qnil;
 	}
 	return rb_equal(str2, str1);
     }