jta resource recovery problem

Hi all,
i noticed that there is some problems with the transaction recovery in JBOSS.
When a number of warnings like this : "WARN oggerI18N om.arjuna.ats.internal.jta.resources.arjunacore.norecoveryxa om.arjuna.ats.internal.jta.resources.arjunacore.norecoveryxa Could not find new XAResource to use for recovering non-serializable XAResource" appear , at some time the exceptions mechanism is affected (the exceptions are not thrown anymore). If the application uses timers those are also blocked (the timeouts dont appear anymore), it seems that the transcations that are not finished are blocking the timers. Why aren't those transactions just ended after some specific time ? Or is there another way to deal with the situation ?

Thanks in advance, Nicu