diff --git a/hibernate-core/src/main/java/org/hibernate/internal/log/DeprecationLogger.java b/hibernate-core/src/main/java/org/hibernate/internal/log/DeprecationLogger.java
index 196bd256fa..d53887e479 100644
--- a/hibernate-core/src/main/java/org/hibernate/internal/log/DeprecationLogger.java
+++ b/hibernate-core/src/main/java/org/hibernate/internal/log/DeprecationLogger.java
@@ -208,5 +208,14 @@ public interface DeprecationLogger extends BasicLogger {
 	)
 	void logDeprecatedBytecodeEnhancement();
 
+	@LogMessage(level = WARN)
+	@Message(
+			id = 90000020,
+			value = "You are using the deprecated legacy bytecode enhancement Ant-task.  This task is left in place for a short-time to " +
+					"aid migrations to 5.1 and the new (vastly improved) bytecode enhancement support.  This task (%s) now delegates to the" +
+					"new Ant-task (%s) leveraging that new bytecode enhancement.  You should update your build to use the new task explicitly."
+	)
+	void logDeprecatedInstrumentTask(Class taskClass, Class newTaskClass);
+
 
 }
diff --git a/hibernate-core/src/main/java/org/hibernate/tool/instrument/javassist/InstrumentTask.java b/hibernate-core/src/main/java/org/hibernate/tool/instrument/javassist/InstrumentTask.java
index 2f082bfbb8..f617a39700 100644
--- a/hibernate-core/src/main/java/org/hibernate/tool/instrument/javassist/InstrumentTask.java
+++ b/hibernate-core/src/main/java/org/hibernate/tool/instrument/javassist/InstrumentTask.java
@@ -6,49 +6,29 @@
  */
 package org.hibernate.tool.instrument.javassist;
 
-import org.hibernate.bytecode.buildtime.internal.JavassistInstrumenter;
-import org.hibernate.bytecode.buildtime.spi.Instrumenter;
-import org.hibernate.bytecode.buildtime.spi.Logger;
-import org.hibernate.tool.instrument.BasicInstrumentationTask;
+import org.hibernate.internal.log.DeprecationLogger;
+import org.hibernate.tool.enhance.EnhancementTask;
 
 /**
- * An Ant task for instrumenting persistent classes in order to enable
- * field-level interception using Javassist.
- * <p/>
- * In order to use this task, typically you would define a a taskdef
- * similiar to:<pre>
- * <taskdef name="instrument" classname="org.hibernate.tool.instrument.javassist.InstrumentTask">
- *     <classpath refid="lib.class.path"/>
- * </taskdef>
- * </pre>
- * where <tt>lib.class.path</tt> is an ANT path reference containing all the
- * required Hibernate and Javassist libraries.
- * <p/>
- * And then use it like:<pre>
- * <instrument verbose="true">
- *     <fileset dir="${testclasses.dir}/org/hibernate/test">
- *         <include name="yadda/yadda/**"/>
- *         ...
- *     </fileset>
- * </instrument>
- * </pre>
- * where the nested ANT fileset includes the class you would like to have
- * instrumented.
- * <p/>
- * Optionally you can chose to enable "Extended Instrumentation" if desired
- * by specifying the extended attriubute on the task:<pre>
- * <instrument verbose="true" extended="true">
- *     ...
- * </instrument>
- * </pre>
- * See the Hibernate manual regarding this option.
+ * This is the legacy Ant-task Hibernate provided historically to
+ * perform its old-school bytecode instrumentation.  That has been replaced wholesale
+ * with a new approach to bytecode manipulation offering 3 build-time variations for Ant,
+ * Maven and Gradle.
  *
  * @author Muga Nishizawa
  * @author Steve Ebersole
+ *
+ * @deprecated This is the legacy Ant-task Hibernate provided historically to
+ * perform its old-school bytecode instrumentation.  That has been replaced wholesale
+ * with a new approach to bytecode manipulation offering 3 build-time variations for Ant,
+ * Maven and Gradle.
+ *
+ * @see EnhancementTask
  */
-public class InstrumentTask extends BasicInstrumentationTask {
-	@Override
-	protected Instrumenter buildInstrumenter(Logger logger, Instrumenter.Options options) {
-		return new JavassistInstrumenter( logger, options );
+@Deprecated
+@SuppressWarnings("unused")
+public class InstrumentTask extends EnhancementTask {
+	public InstrumentTask() {
+		DeprecationLogger.DEPRECATION_LOGGER.logDeprecatedInstrumentTask( InstrumentTask.class, EnhancementTask.class );
 	}
-}
+}
\ No newline at end of file