diff --git a/ChangeLog b/ChangeLog
index 419eed8d7b..5d67e2a49a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Apr 22 21:50:17 2010  Keiju Ishitsuka  <keiju@ruby-lang.org>
+
+	* lib/irb/ext/multi-irb.rb: fix multi-irb running
+	  parallelly. [ruby-dev:41031] [Bug #3182]
+
 Thu Apr 22 17:13:34 2010  Eric Hodel  <drbrain@segment7.net>
 
 	* lib/rubygems: Import RubyGems 1.3.7.pre.1 (as 1.3.6.1).
diff --git a/lib/irb/ext/multi-irb.rb b/lib/irb/ext/multi-irb.rb
index 7bb1a7cfab..0152d38ffd 100644
--- a/lib/irb/ext/multi-irb.rb
+++ b/lib/irb/ext/multi-irb.rb
@@ -172,12 +172,14 @@ module IRB
       ensure
 	unless system_exit
 	  @JobManager.delete(irb)
-	  if parent_thread.alive?
-	    @JobManager.current_job = @JobManager.irb(parent_thread)
-	    parent_thread.run
-	  else
-	    @JobManager.current_job = @JobManager.main_irb
-	    @JobManager.main_thread.run
+	  if @JobManager.current_job == irb
+	    if parent_thread.alive?
+	      @JobManager.current_job = @JobManager.irb(parent_thread)
+	      parent_thread.run
+	    else
+	      @JobManager.current_job = @JobManager.main_irb
+	      @JobManager.main_thread.run
+	    end
 	  end
 	end
       end