Manik, In jboss.cache.UnversionedNode.java, when it is a singletonMap the mapping will be dropped when remove(K key) is called, no matter if the key matches. This is in trunk and at least 3.0.2.GA. public V remove(K key) { if (data == null) return null; V value; if (data instanceof FastCopyHashMap) { value = data.remove(key); downgradeDataMapIfNeeded(); } else { // singleton maps cannot remove! value = data.get(key); data = null; } return value; } Should I file a bug and fix it or you are going to fix it? Thanks, -Alex View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4208654#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...