@PrePersist misses (partly) the point

As supposed in the Wiki I implemented a lastChange timestamp. Now I found out by accidence that the @PrePersist annotated method is called many times more. If you have a look at the call chain it is clear why:

The prePersist-method is called everytime an object gets mapped to a DBObject. This is not totally bad since it works in most cases: The update doesn't care if the lastChange field is not persisted. Nevertheless I stumbled over following case where I ran into problems:

• There is an entity (Application) with an embedded list of children (UsageData).
• The children (UsageData) have a lastChange-field as shown in the Wiki.
• You want to remove a certain child from the list. Pseudocode (deriving from BasicDAO):

    Query<Application> query = createQuery().field("_id").equal(applicationId);
    UpdateOperations<Application> updateOps = createUpdateOperations();
    updateOps.removeAll("usageDataList", usageDataToRemove);
    update(query, updateOps)

• The remove of the child does never work since the lastChange-field gets updated in the callstack of removeAll. Problem is, that the database do only remove the embedded children which are field-by-field-compared equal. Since the lastChange field got updated by @PrePersist the usageData in the database and in the DBObject provided do always differ!

Is there an easy workaround?
(In my case I gonna try to avoid @PrePersist here...)

Start with the LifecycleMethods wiki guidance and the BasicDAO update/removeAll path described in the issue. Trace where @PrePersist runs while embedded UsageData is mapped, then reproduce removal of a child whose lastChange changes during mapping. Done means the intended behavior or workaround is established so removeAll can match and remove the embedded child reliably.