diff --git a/assignments/build.xml b/assignments/build.xml
index 3135918eee4f35fb7a80c43ec8bcc205bfbeb119..0d34721a796d0f04a276f75c8b606601bd7ff1e1 100644
--- a/assignments/build.xml
+++ b/assignments/build.xml
@@ -130,9 +130,9 @@ POSSIBILITY OF SUCH DAMAGE.
     </target>
     
     <!-- ensure backwards compatibility of produced jar to specified version of Java, though project itself may be higher -->
-    <property name="java.source"                 value="17"/><!-- LTS -->
-    <property name="java.target"                 value="17"/><!-- LTS -->
-    <property name="java.release"                value="17"/><!-- LTS --><!-- simpler, less verbose than -source -target -->
+    <!-- <property name="java.source"                 value="21"/>LTS -->
+    <!-- <property name="java.target"                 value="21"/>LTS -->
+    <!-- <property name="java.release"                value="21"/>LTS --><!-- simpler, less verbose than -source -target -->
     <property name="dist.javadoc.dir"            value="dist/javadoc"/>
     
     <property name="javadoc.additionalparam" value=""/>
diff --git a/examples/build.xml b/examples/build.xml
index 79c4849bf30c42f1f4c24d95c4141e34895d0afc..dab94d25d33cd12861a32de0d8a1ea1ca626b572 100644
--- a/examples/build.xml
+++ b/examples/build.xml
@@ -134,9 +134,9 @@ POSSIBILITY OF SUCH DAMAGE.
     </target>
     
     <!-- ensure backwards compatibility of produced jar to specified version of Java, though project itself may be higher -->
-    <property name="java.source"                 value="17"/><!-- LTS -->
-    <property name="java.target"                 value="17"/><!-- LTS -->
-    <property name="java.release"                value="17"/><!-- LTS --><!-- simpler, less verbose than -source -target -->
+    <!-- <property name="java.source"                 value="21"/>LTS -->
+    <!-- <property name="java.target"                 value="21"/>LTS -->
+    <!-- <property name="java.release"                value="21"/>LTS --><!-- simpler, less verbose than -source -target -->
     <property name="dist.javadoc.dir"            value="dist/javadoc"/>
     
     <property name="javadoc.additionalparam" value=""/>