Error when updating rules / strategy

2014/05/20 13:41:35,072 INFO  [app.server.service.ExternalRestServicesImpl] (pool-3172-thread-1) Reseted the Strategy with id 4028e494461124c81461384262701a
2014/05/20 13:41:35,221 INFO  [app.server.service.StrategyServiceImpl] (pool-3172-thread-1) ## Success! New Crosses strategy has been restarted successfully
2014/05/20 13:42:15,043 WARN  [EventDispatcher] (http-127.1.244.129-127.1.244.129-8080-9) client tried to register a non-portable type: class java.lang.Boolean
2014/05/20 13:42:23,527 ERROR [app.server.persistence.CommonDAO] (http-127.1.244.129-127.1.244.129-8080-9) Can't execute query UPDATE Strategy s SET s.modifiedDate=:md WHERE id=:sid: javax.persistence.PersistenceException: org.hibernate.HibernateException: Found shared references to a collection: com.magick.models.shared.Strategy.rules
2014/05/20 13:42:23,733 INFO  [app.server.service.interceptor.WatchInterceptor] (http-127.1.244.129-127.1.244.129-8080-9) Intercepted, required activity log: com.magick.models.shared.log.RuleActivity - Rule updated
2014/05/20 13:42:23,735 INFO  [app.server.service.interceptor.helper.ActivityInterceptorHelper] (http-127.1.244.129-127.1.244.129-8080-9) Activity Interceptor Helper
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2014/05/20 13:45:32,588 WARN  [EventDispatcher] (http-127.1.244.129-127.1.244.129-8080-9) client tried to register a non-portable type: class java.lang.Boolean
2014/05/20 13:45:40,656 INFO  [app.server.service.StrategyServiceImpl] (http-127.1.244.129-127.1.244.129-8080-4) Getting strategies for user testuser6
2014/05/20 13:45:41,322 ERROR [app.server.persistence.CommonDAO] (http-127.1.244.129-127.1.244.129-8080-11) Can't execute query UPDATE Strategy s SET s.modifiedDate=:md WHERE id=:sid: javax.persistence.PersistenceException: org.hibernate.HibernateException: Found shared references to a collection: com.magick.models.shared.Strategy.rules