diff --git a/ChangeLog b/ChangeLog
index 4ca02ddf87..d2330e440a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Feb  6 19:04:32 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* re.c (rb_reg_initialize_m): shoule not preset "kcode" unless
+	  encoding is explicitly specified.
+
 Thu Feb  6 19:01:32 2003  Minero Aoki  <aamine@loveruby.net>
 
 	* lib/fileutils.rb: new method FileUtils.pwd.
diff --git a/re.c b/re.c
index b837da8c3f..4b8c821d2b 100644
--- a/re.c
+++ b/re.c
@@ -1239,21 +1239,23 @@ rb_reg_initialize_m(argc, argv, self)
 	}
 	rb_reg_check(argv[0]);
 	flags = RREGEXP(argv[0])->ptr->options & 0xf;
-	switch (RBASIC(argv[0])->flags & KCODE_MASK) {
-	  case KCODE_NONE:
-	    flags |= 16;
-	    break;
-	  case KCODE_EUC:
-	    flags |= 32;
-	    break;
-	  case KCODE_SJIS:
-	    flags |= 48;
-	    break;
-	  case KCODE_UTF8:
-	    flags |= 64;
-	    break;
-	  default:
-	    break;
+	if (FL_TEST(argv[0], KCODE_FIXED)) {
+	    switch (RBASIC(argv[0])->flags & KCODE_MASK) {
+	      case KCODE_NONE:
+		flags |= 16;
+		break;
+	      case KCODE_EUC:
+		flags |= 32;
+		break;
+	      case KCODE_SJIS:
+		flags |= 48;
+		break;
+	      case KCODE_UTF8:
+		flags |= 64;
+		break;
+	      default:
+		break;
+	    }
 	}
 	s = RREGEXP(argv[0])->str;
 	len = RREGEXP(argv[0])->len;