Mixing of data among custom thread scoped beans

[Nader Aeinehchi]

Problem:
Child threads get wrong custom thread scoped beans.

Background
I have created a custom thread scoped based on the doucmentation in section 4.4.5:
http://static.springsource.org/sprin...l/ch04s04.html

The underlying implementation uses a CopyBasedInheritableThreadLocal to store Attributes:

final CopyBasedInheritableThreadLocal<Attributes> holder = new CopyBasedInheritableThreadLocal<Attributes>(true)

Proper locking has been enforced to ensure thread safety. The child threads inherit a copy of the scoped bean such that child threads do not need to make additional locking/synchronization on the bean.

    public CopyBasedInheritableThreadLocal(final boolean childThreadGetsCopy) {
        this.childThreadGetsCopy = childThreadGetsCopy;
    }

    @Override
    protected T childValue(T parentValue) {

        if (!childThreadGetsCopy) {
            return parentValue;
        }

        /*
         * Note that null does not pass the following check, and will thus does not throw NullPointerException. 
         */
        if (parentValue instanceof Copyable) {
            return ((Copyable<T>) parentValue).copy();
        }
        return parentValue;
    }

In my application, the main thread (we request) sends tasks to a thread pool (ExecutorService). Then each child thread (which comes from the thread pool) asks for the custom thread scoped bean.

In a POJO environment, I would typically remove objects from the thread local variable in the beginning of a request to ensure no dirty data exist in the thread.

1. I do not know exactly how to do it with Spring?
2. Shall I write some destruction callback?
3. Can the problem be related to thread pool in which a thread retrieved from thread pool is not a child thread of the thread that originally initialized the bean?

In advance, thanks for any help.