diff --git a/ChangeLog b/ChangeLog
index a4685b0851..222f41f263 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Tue Apr 17 21:35:47 2012  Kouhei Sutou  <kou@cozmixng.org>
+
+	* lib/rexml/parsers/baseparser.rb, test/rexml/test_namespace.rb:
+	  fix the default xml namespace URI validation.
+	  [ruby-dev:45169] [Bug #5956]
+	  Reported by Miho Hiramatsu. Thanks!!!
+
 Mon Apr 17 14:27:22 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* dln.c (rb_w32_check_imported): skip ordinal entries.  based on a
diff --git a/lib/rexml/parsers/baseparser.rb b/lib/rexml/parsers/baseparser.rb
index 612245fb73..95afd7add5 100644
--- a/lib/rexml/parsers/baseparser.rb
+++ b/lib/rexml/parsers/baseparser.rb
@@ -376,7 +376,7 @@ module REXML
                 attrs.each { |a,b,c,d,e|
                   if b == "xmlns"
                     if c == "xml"
-                      if d != "http://www.w3.org/XML/1998/namespace"
+                      if e != "http://www.w3.org/XML/1998/namespace"
                         msg = "The 'xml' prefix must not be bound to any other namespace "+
                         "(http://www.w3.org/TR/REC-xml-names/#ns-decl)"
                         raise REXML::ParseException.new( msg, @source, self )
diff --git a/test/rexml/test_namespace.rb b/test/rexml/test_namespace.rb
new file mode 100644
index 0000000000..6ab16b6342
--- /dev/null
+++ b/test/rexml/test_namespace.rb
@@ -0,0 +1,38 @@
+require "rexml_test_utils"
+
+require "rexml/document"
+
+class TestNamespace < Test::Unit::TestCase
+  include REXMLTestUtils
+  include REXML
+
+  def setup
+    @xsa_source = <<-EOL
+      <?xml version="1.0"?>
+      <?xsl stylesheet="blah.xsl"?>
+      <!-- The first line tests the XMLDecl, the second tests PI.
+      The next line tests DocType. This line tests comments. -->
+      <!DOCTYPE xsa PUBLIC
+        "-//LM Garshol//DTD XML Software Autoupdate 1.0//EN//XML"
+        "http://www.garshol.priv.no/download/xsa/xsa.dtd">
+
+      <xsa>
+        <vendor id="blah">
+          <name>Lars Marius Garshol</name>
+          <email>larsga@garshol.priv.no</email>
+          <url>http://www.stud.ifi.uio.no/~lmariusg/</url>
+        </vendor>
+      </xsa>
+    EOL
+  end
+
+  def test_xml_namespace
+    xml = <<-XML
+<?xml version="1.0" encoding="UTF-8"?>
+<root xmlns:xml="http://www.w3.org/XML/1998/namespace" />
+XML
+    document = Document.new(xml)
+    assert_equal("http://www.w3.org/XML/1998/namespace",
+                 document.root.namespace("xml"))
+  end
+end
diff --git a/version.h b/version.h
index 67381b8500..4244aee1cf 100644
--- a/version.h
+++ b/version.h
@@ -1,5 +1,5 @@
 #define RUBY_VERSION "1.9.3"
-#define RUBY_PATCHLEVEL 187
+#define RUBY_PATCHLEVEL 188
 
 #define RUBY_RELEASE_DATE "2012-04-17"
 #define RUBY_RELEASE_YEAR 2012