diff --git a/WHATSNEW b/WHATSNEW
index 925349653..517d8cec9 100644
--- a/WHATSNEW
+++ b/WHATSNEW
@@ -234,6 +234,8 @@ Fixed bugs:
 * <unzip> and <untar> could leave file handles open on invalid
   archives.  Bugzilla report 34893.
 
+* propertyset threw NPE with nested, mapped propertysets.
+
 Other changes:
 --------------
 
diff --git a/src/etc/testcases/types/propertyset.xml b/src/etc/testcases/types/propertyset.xml
index 68ce6c23a..3c2d2d8e3 100644
--- a/src/etc/testcases/types/propertyset.xml
+++ b/src/etc/testcases/types/propertyset.xml
@@ -52,4 +52,43 @@
       exp="barB=BarB, fooA=FooA"
       got="${toString:my-set}"/>
   </target>
+
+  <target name="nested-mapped">
+    <propertyset id="nested-mapped">
+      <propertyset>
+        <propertyset refid="properties-starting-with-foo"/>
+        <globmapper from="foo*" to="boo*" />
+      </propertyset>
+      <propertyset>
+        <propertyset refid="properties-starting-with-bar"/>
+        <globmapper from="bar*" to="far*" />
+      </propertyset>
+    </propertyset>
+    <expect.equals
+      test="nested mapped propertysets"
+      exp="booA=FooA, farB=BarB"
+      got="${toString:nested-mapped}"/>
+  </target>
+
+  <target name="nested-mapped-mapped">
+    <propertyset id="nested-mapped-mapped">
+      <propertyset>
+        <propertyset refid="properties-starting-with-foo"/>
+        <globmapper from="foo*" to="boo*" />
+      </propertyset>
+      <propertyset>
+        <propertyset refid="properties-starting-with-bar"/>
+        <globmapper from="bar*" to="far*" />
+      </propertyset>
+      <mapper>
+        <globmapper from="boo*" to="hoo*" />
+        <globmapper from="far*" to="near*" />
+      </mapper>
+    </propertyset>
+    <expect.equals
+      test="nested mapped propertysets"
+      exp="hooA=FooA, nearB=BarB"
+      got="${toString:nested-mapped-mapped}"/>
+  </target>
+
 </project>
diff --git a/src/main/org/apache/tools/ant/types/PropertySet.java b/src/main/org/apache/tools/ant/types/PropertySet.java
index a4710c017..4b6f19a36 100644
--- a/src/main/org/apache/tools/ant/types/PropertySet.java
+++ b/src/main/org/apache/tools/ant/types/PropertySet.java
@@ -282,6 +282,12 @@ public class PropertySet extends DataType {
         Hashtable props =
             prj == null ? getAllSystemProperties() : prj.getProperties();
 
+        //quick & dirty, to make nested mapped p-sets work:
+        for (Enumeration e = setRefs.elements(); e.hasMoreElements();) {
+            PropertySet set = (PropertySet) e.nextElement();
+            props.putAll(set.getProperties());
+        }
+
         if (getDynamic() || cachedNames == null) {
             names = new HashSet();
             addPropertyNames(names, props);
@@ -382,20 +388,7 @@ public class PropertySet extends DataType {
      * @return the referenced PropertySet.
      */
     protected PropertySet getRef() {
-        if (!isChecked()) {
-            Stack stk = new Stack();
-            stk.push(this);
-            dieOnCircularReference(stk, getProject());
-        }
-
-        Object o = getRefid().getReferencedObject(getProject());
-        if (!(o instanceof PropertySet)) {
-            String msg = getRefid().getRefId()
-                + " doesn\'t denote a propertyset";
-            throw new BuildException(msg);
-        } else {
-            return (PropertySet) o;
-        }
+        return (PropertySet) getCheckedRef(PropertySet.class, "propertyset");
     }
 
     /**
@@ -469,4 +462,5 @@ public class PropertySet extends DataType {
         }
         return b.toString();
     }
+
 }
diff --git a/src/testcases/org/apache/tools/ant/types/PropertySetTest.java b/src/testcases/org/apache/tools/ant/types/PropertySetTest.java
index b30dd3ca0..28164e7c4 100644
--- a/src/testcases/org/apache/tools/ant/types/PropertySetTest.java
+++ b/src/testcases/org/apache/tools/ant/types/PropertySetTest.java
@@ -36,4 +36,12 @@ public class PropertySetTest extends BuildFileTest {
     public void testReferenceToTwoReferences() {
         executeTarget("reference-to-two-references");
     }
+
+    public void testNestedMapped() {
+        executeTarget("nested-mapped");
+    }
+
+    public void testNestedMappedMapped() {
+        executeTarget("nested-mapped-mapped");
+    }
 }