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diff --git a/src/main/java/org/apache/commons/math/ode/jacobians/StepHandlerWithJacobians.java b/src/main/java/org/apache/commons/math/ode/jacobians/StepHandlerWithJacobians.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.math.ode.jacobians;
+
+import org.apache.commons.math.ode.DerivativeException;
+
+/**
+ * This interface represents a handler that should be called after
+ * each successful step.
+ *
+ * <p>The ODE integrators compute the evolution of the state vector at
+ * some grid points that depend on their own internal algorithm. Once
+ * they have found a new grid point (possibly after having computed
+ * several evaluation of the derivative at intermediate points), they
+ * provide it to objects implementing this interface. These objects
+ * typically either ignore the intermediate steps and wait for the
+ * last one, store the points in an ephemeris, or forward them to
+ * specialized processing or output methods.</p>
+ *
+ * <p>Note that is is possible to register a {@link
+ * org.apache.commons.math.ode.sampling.StepHandler classical step handler}
+ * in the low level integrator used to build a {@link FirstOrderIntegratorWithJacobians}
+ * rather than implementing this class. The step handlers registered at low level
+ * will see the big compound state whether the step handlers defined by this interface
+ * see the original state, and its jacobians in separate arrays.</p>
+ *
+ * <p>The compound state is guaranteed to contain the original state in the first
+ * elements, followed by the jacobian with respect to initial state (in row order),
+ * followed by the jacobian with respect to parameters (in row order). If for example
+ * the original state dimension is 6 and there are 3 parameters, the compound state will
+ * be a 60 elements array. The first 6 elements will be the original state, the next 36
+ * elements will be the jacobian with respect to initial state, and the remaining 18 elements
+ * will be the jacobian with respect to parameters.</p>
+ *
+ * <p>Dealing with low level step handlers is cumbersome if one really needs the jacobians
+ * in these methods, but it also prevents many data being copied back and forth between
+ * state and jacobians on one side and compound state on the other side. So for performance
+ * reasons, it is recommended to use this interface <em>only</em> if jacobians are really
+ * needed and to use lower level handlers if only state is needed.</p>
+ *
+ * @see FirstOrderIntegratorWithJacobians
+ * @see StepInterpolatorWithJacobians
+ * @version $Revision: 1073158 $ $Date: 2011-02-21 22:46:52 +0100 (lun. 21 févr. 2011) $
+ * @since 2.1
+ * @deprecated as of 2.2 the complete package is deprecated, it will be replaced
+ * in 3.0 by a completely rewritten implementation
+ */
+@Deprecated
+public interface StepHandlerWithJacobians {
+
+  /** Determines whether this handler needs dense output.
+   * <p>This method allows the integrator to avoid performing extra
+   * computation if the handler does not need dense output.</p>
+   * @return true if the handler needs dense output
+   */
+  boolean requiresDenseOutput();
+
+  /** Reset the step handler.
+   * Initialize the internal data as required before the first step is
+   * handled.
+   */
+  void reset();
+
+  /**
+   * Handle the last accepted step
+   * @param interpolator interpolator for the last accepted step. For
+   * efficiency purposes, the various integrators reuse the same
+   * object on each call, so if the instance wants to keep it across
+   * all calls (for example to provide at the end of the integration a
+   * continuous model valid throughout the integration range, as the
+   * {@link org.apache.commons.math.ode.ContinuousOutputModel
+   * ContinuousOutputModel} class does), it should build a local copy
+   * using the clone method of the interpolator and store this copy.
+   * Keeping only a reference to the interpolator and reusing it will
+   * result in unpredictable behavior (potentially crashing the application).
+   * @param isLast true if the step is the last one
+   * @throws DerivativeException this exception is propagated to the
+   * caller if the underlying user function triggers one
+   */
+  void handleStep(StepInterpolatorWithJacobians interpolator, boolean isLast) throws DerivativeException;
+
+}