PersistentObject hangs when committing

Device: RIM BlackBerry 8830
Software Version: 4.2.2.x

Problem: storing a Double/Float object would hang when committing
i.e.
set(123456789L, new Double(2.0));
set(123456789L, new Float(2.0));

even a Hashtable containing Double/Float would hang also
i.e.
Hashtable ht = new Hashtable();
ht.add("key",new Double(2.0));
set(123456789L, ht);

here is the code snippet:

public void set(long key, Object value) {
    PersistentObject store = PersistentStore.getPersistentObject(key);
    store.setContents(value);
    System.out.println("Before commit");
    store.commit();
    System.out.println("After commit);
}

Solution: store something else

i.e.
set(123456789L, Double.toString(2.0));
set(123456789L, Float.toString(2.0));
set(123456789L, new Integer(2));
set(123456789L, Boolean.TRUE);
set(123456789L, new Long(2));
set(123456789L, new Short((short)2));