diff --git a/pmd-netbeans/lib/backport-util-concurrent.jar b/pmd-netbeans/lib/backport-util-concurrent.jar
deleted file mode 100644
index 99f9b9c6a3..0000000000
Binary files a/pmd-netbeans/lib/backport-util-concurrent.jar and /dev/null differ
diff --git a/pmd-netbeans/lib/jaxen-1.1-beta-10.jar b/pmd-netbeans/lib/jaxen-1.1.jar
similarity index 55%
rename from pmd-netbeans/lib/jaxen-1.1-beta-10.jar
rename to pmd-netbeans/lib/jaxen-1.1.jar
index 69b45d7a43..821519245b 100644
Binary files a/pmd-netbeans/lib/jaxen-1.1-beta-10.jar and b/pmd-netbeans/lib/jaxen-1.1.jar differ
diff --git a/pmd-netbeans/lib/pmd-3.9.jar b/pmd-netbeans/lib/pmd-3.9.jar
deleted file mode 100644
index 5006cbea02..0000000000
Binary files a/pmd-netbeans/lib/pmd-3.9.jar and /dev/null differ
diff --git a/pmd-netbeans/lib/pmd-4.0.jar b/pmd-netbeans/lib/pmd-4.0.jar
new file mode 100644
index 0000000000..c204b18356
Binary files /dev/null and b/pmd-netbeans/lib/pmd-4.0.jar differ
diff --git a/pmd-netbeans/nbproject/project.properties b/pmd-netbeans/nbproject/project.properties
index 8eae133e7d..8c7149b275 100644
--- a/pmd-netbeans/nbproject/project.properties
+++ b/pmd-netbeans/nbproject/project.properties
@@ -1,7 +1,6 @@
 extra.module.files=\
-  modules/ext/jaxen-1.1-beta-10.jar \
-  modules/ext/pmd-3.9.jar \
-  modules/ext/backport-util-concurrent.jar \
+  modules/ext/jaxen-1.1.jar \
+  modules/ext/pmd-4.0.jar \
   modules/ext/asm-3.0.jar \
   modules/ext/nbpmdrules.jar 
 javac.compilerargs=-Xlint:unchecked
diff --git a/pmd-netbeans/nbproject/project.xml b/pmd-netbeans/nbproject/project.xml
index 71d65abb43..14511be556 100644
--- a/pmd-netbeans/nbproject/project.xml
+++ b/pmd-netbeans/nbproject/project.xml
@@ -13,16 +13,12 @@
                 <binary-origin>lib/asm-3.0.jar</binary-origin>
             </class-path-extension>
             <class-path-extension>
-                <runtime-relative-path>ext/backport-util-concurrent.jar</runtime-relative-path>
-                <binary-origin>lib/backport-util-concurrent.jar</binary-origin>
+                <runtime-relative-path>ext/jaxen-1.1.jar</runtime-relative-path>
+                <binary-origin>lib/jaxen-1.1.jar</binary-origin>
             </class-path-extension>
             <class-path-extension>
-                <runtime-relative-path>ext/jaxen-1.1-beta-10.jar</runtime-relative-path>
-                <binary-origin>lib/jaxen-1.1-beta-10.jar</binary-origin>
-            </class-path-extension>
-            <class-path-extension>
-                <runtime-relative-path>ext/pmd-3.9.jar</runtime-relative-path>
-                <binary-origin>lib/pmd-3.9.jar</binary-origin>
+                <runtime-relative-path>ext/pmd-4.0.jar</runtime-relative-path>
+                <binary-origin>lib/pmd-4.0.jar</binary-origin>
             </class-path-extension>
             <class-path-extension>
                 <!-- Deployed path, relative to dir containing module: -->
@@ -193,7 +189,7 @@
             <public-packages/>
             <extra-compilation-unit>
                 <package-root>libsrc</package-root>
-                <classpath>lib/pmd-3.9.jar</classpath>
+                <classpath>lib/pmd-4.0.jar</classpath>
                 <built-to>build/libclasses</built-to>
                 <built-to>${cluster}/modules/ext/nbpmdrules.jar</built-to>
             </extra-compilation-unit>
diff --git a/pmd-netbeans/src/pmd/scan/Scanner.java b/pmd-netbeans/src/pmd/scan/Scanner.java
index 8edbfa69d2..4d4b022aab 100644
--- a/pmd-netbeans/src/pmd/scan/Scanner.java
+++ b/pmd-netbeans/src/pmd/scan/Scanner.java
@@ -91,6 +91,9 @@ public class Scanner implements CancellableTask<CompilationInfo> {
             LOG.fine(toString() + "started");
             cancelled = false;
             Document doc = info.getDocument();
+            if (doc == null) {
+                return;
+            }
             
             int tabSize = 8;
             if (doc instanceof BaseDocument) {
@@ -107,7 +110,7 @@ public class Scanner implements CancellableTask<CompilationInfo> {
                 return;
             }
             
-            LineCookie cookie = ( LineCookie )dobj.getCookie( LineCookie.class );
+            LineCookie cookie = dobj.getCookie(LineCookie.class);
             Line.Set lineset = cookie.getLineSet();
             List<DataObject> list = Collections.singletonList(dobj);
             // TODO try to avoid duplicate work in this method