diff --git a/testsrc/jstests/577141.jstest b/testsrc/jstests/577141.jstest
new file mode 100644
index 0000000000..b3fc843597
--- /dev/null
+++ b/testsrc/jstests/577141.jstest
@@ -0,0 +1,4 @@
+var ns = new Namespace( "dc", "http://purl.org/dc/elements/1.1" );
+var x = new XML( "<something/>" );
+x.setNamespace( ns );
+"success";
diff --git a/xmlimplsrc/build.xml b/xmlimplsrc/build.xml
index 15535b85e9..8f9276ef12 100644
--- a/xmlimplsrc/build.xml
+++ b/xmlimplsrc/build.xml
@@ -147,7 +147,7 @@
   <target name="xmlbeans-get" unless="xmlbeans-zip-present?">
     <property
       name="xmlbeans.url"
-      value="http://www.apache.org/dist/xmlbeans/binaries/xmlbeans-2.2.0.zip"
+      value="http://www.apache.org/dist/xmlbeans/binaries/xmlbeans-2.5.0.zip"
     />
 
     <mkdir dir="${xmlbeans.tmp}" />
@@ -157,8 +157,8 @@
   <target name="xmlbeans-unzip" unless="xmlbeans-present?">
     <antcall target="xmlbeans-get" />
     <unzip src="${xmlbeans.zip}" dest="${xmlbeans.tmp}" />
-    <copy tofile="${xbean.jar}" file="${xmlbeans.tmp}/xmlbeans-2.2.0/lib/xbean.jar" />
-    <copy tofile="${jsr173.jar}" file="${xmlbeans.tmp}/xmlbeans-2.2.0/lib/jsr173_1.0_api.jar" />
+    <copy tofile="${xbean.jar}" file="${xmlbeans.tmp}/xmlbeans-2.5.0/lib/xbean.jar" />
+    <copy tofile="${jsr173.jar}" file="${xmlbeans.tmp}/xmlbeans-2.5.0/lib/jsr173_1.0_api.jar" />
     <delete dir="${xmlbeans.tmp}" />
   </target>
 </project>
diff --git a/xmlimplsrc/org/mozilla/javascript/xmlimpl/QName.java b/xmlimplsrc/org/mozilla/javascript/xmlimpl/QName.java
index d4cb149451..7c124c8b87 100644
--- a/xmlimplsrc/org/mozilla/javascript/xmlimpl/QName.java
+++ b/xmlimplsrc/org/mozilla/javascript/xmlimpl/QName.java
@@ -292,7 +292,7 @@ QName newQName(XMLLibImpl lib, String q_uri, String q_localName, String q_prefix
         }
         XmlNode.Namespace ns = null;
         if (q_prefix != null) {
-            ns = XmlNode.Namespace.create(q_uri, q_prefix);
+            ns = XmlNode.Namespace.create(q_prefix, q_uri);
         } else if (q_uri != null) {
             ns = XmlNode.Namespace.create(q_uri);
         } else {