diff --git a/ChangeLog b/ChangeLog
index 0df214d24e..5d7b08dd0c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Tue Apr 22 09:20:40 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* parse.y (arg_ambiguous): hopefully better message.
+
+	* lib/cgi.rb (CGI::QueryExtension::initialize_query): to_ary
+
 Tue Apr 22 06:06:22 2003  Tanaka Akira  <akr@m17n.org>
 
         * lib/resolv.rb (Resolv::DNS::Resource#hash): use XOR to accumulate
diff --git a/lib/cgi.rb b/lib/cgi.rb
index 2e18bfd20d..7dffdd9a33 100644
--- a/lib/cgi.rb
+++ b/lib/cgi.rb
@@ -941,27 +941,23 @@ convert string charset, and set language to "ja".
     end
     private :initialize_query
 
-    def [](key)
-      value, = @params[key]
-      unless value.nil?
-	value = value.dup
-	def value.to_ary
-	  [self]
-	end
-	def value.[](key)
+    class Value < String
+      def [](key)
 	  $stderr.puts <<END
 CAUTION! cgi['key'] == cgi.params['key'][0] If want Array, use cgi.params['key']
 END
 	  self
-	end
-	def value.first
-	  $stderr.puts <<END
-CAUTION! cgi['key'] == cgi.params['key'][0] If want Array, use cgi.params['key']
-END
-	  self
-	end
       end
-      value
+      def first
+	  $stderr.puts <<END
+CAUTION! cgi['key'] == cgi.params['key'][0] If want Array, use cgi.params['key']
+END
+	  self
+      end
+    end
+
+    def [](key)
+      Value.new(@params[key][0])
     end
 
     def keys(*args)
diff --git a/lib/rational.rb b/lib/rational.rb
index e63e8c4814..0c784fb94b 100644
--- a/lib/rational.rb
+++ b/lib/rational.rb
@@ -67,7 +67,9 @@ class Rational < Numeric
   def Rational.new!(num, den = 1)
     new(num, den)
   end
-  
+
+  private_class_method :new
+
   def initialize(num, den)
     if den < 0
       num = -num
diff --git a/parse.y b/parse.y
index 8d8ad5e3e2..2ee33381d5 100644
--- a/parse.y
+++ b/parse.y
@@ -3269,7 +3269,7 @@ here_document(here)
 static void
 arg_ambiguous()
 {
-    rb_warning("ambiguous first argument; make sure");
+    rb_warning("ambiguous first argument; put parentheses or even spaces");
 }
 
 #define IS_ARG() (lex_state == EXPR_ARG || lex_state == EXPR_CMDARG)