Ok thx to all. In fact I removed the expiration configuration in the config file and the code. I just added the line suggested by lovelyliatroim and it sounds to work fine I just have warnings in the log file about the different nodes of the FQN where I add my object : anonymous wrote : 2008-09-01 11:01:25,709: WARN [EvictionTimer-0] ExpirationAlgorithm, org.jboss.cache.eviction.ExpirationAlgorithm: No expiration key 'expiration' for Node: /node1 | 2008-09-01 11:01:25,712: WARN [EvictionTimer-0] ExpirationAlgorithm, org.jboss.cache.eviction.ExpirationAlgorithm: No expiration key 'expiration' for Node: /node1/node2 | 2008-09-01 11:01:25,713: WARN [EvictionTimer-0] ExpirationAlgorithm, org.jboss.cache.eviction.ExpirationAlgorithm: No expiration key 'expiration' for Node: /node1/node2/node3 Anyway mircea is right, it should work with my previous code and with the fix (in 3.0.0.GA version), it should be surely possible to set the expiration at the root of a tree or subtree without having to do it again on every sub nodes and object. Tomorow I will add these additionnal note in the consequently created issue. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4173801#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...