diff --git a/ChangeLog b/ChangeLog
index 71d342e187b6d9..f36e3726a0bdc0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Apr 13 13:57:36 2010  Keiju Ishitsuka  <keiju@ruby-lang.org>
+
+	* lib/irb/completion.rb (CompletionProc): fix [ruby-dev:40953]
+	  [Bug #3126]. Thanks Kazuhiro NISHIYAMA.
+
 Tue Apr 13 09:32:12 2010  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* transcode.c (transcode_loop): insert output the value when
diff --git a/lib/irb/completion.rb b/lib/irb/completion.rb
index a345c23af78abb..e059bc40559852 100644
--- a/lib/irb/completion.rb
+++ b/lib/irb/completion.rb
@@ -81,10 +81,10 @@ module InputCompletor
 	candidates.grep(/^#{receiver}/).collect{|e| "::" + e}
 
 #      when /^(((::)?[A-Z][^:.\(]*)+)::?([^:.]*)$/
-      when /^([A-Z].*)::([^:.]+)*$/
+      when /^([A-Z].*)::([^:.]*)$/
 	# Constant or class methods
 	receiver = $1
-	message = Regexp.quote($4)
+	message = Regexp.quote($2)
 	begin
 	  candidates = eval("#{receiver}.constants.collect{|m| m.to_s}", bind)
 	  candidates |= eval("#{receiver}.methods.collect{|m| m.to_s}", bind)
@@ -134,7 +134,7 @@ module InputCompletor
       when /^([^."].*)\.([^.]*)$/
 	# variable
 	receiver = $1
-	message = Regexp.quote($3)
+	message = Regexp.quote($2)
 
 	gv = eval("global_variables", bind).collect{|m| m.to_s}
 	lv = eval("local_variables", bind).collect{|m| m.to_s}