请教高手关于xfire obj映射xml时的问题

在用Xfire做webservice的一个功能时需要返回一个List 于是报以下异常.求高手指点at org.codehaus.xfire.aegis.type.basic.BeanType.writeObject(BeanType.java:392) ~[xfire-all-1.2.6.jar:na]
at org.codehaus.xfire.aegis.type.basic.BeanType.writeObject(BeanType.java:392) ~[xfire-all-1.2.6.jar:na]
at org.codehaus.xfire.aegis.type.basic.BeanType.writeObject(BeanType.java:392) ~[xfire-all-1.2.6.jar:na]
Caused by: java.lang.reflect.InvocationTargetException: null
at sun.reflect.GeneratedMethodAccessor78.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) ~[na:1.6.0_13]
at java.lang.reflect.Method.invoke(Method.java:597) ~[na:1.6.0_13]
at org.codehaus.xfire.aegis.type.basic.BeanType.readProperty(BeanType.java:442) ~[xfire-all-1.2.6.jar:na]
at org.codehaus.xfire.aegis.type.basic.BeanType.writeObject(BeanType.java:377) ~[xfire-all-1.2.6.jar:na]
... 1019 common frames omitted
Caused by: java.lang.StackOverflowError: null
at java.lang.Exception.<init>(Exception.java:77) ~[na:1.6.0_13]
at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:187) ~[hibernate-3.3.2.jar:na]
at com.jeecms.cms.entity.main.CmsSite_$$_javassist_28.getAfterCheck(CmsSite_$$_javassist_28.java) ~[CmsSite.class:na]
at com.jeecms.cms.entity.main.Channel.getAfterCheckEnum(Channel.java:296) ~[Channel.class:na]
at sun.reflect.GeneratedMethodAccessor78.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) ~[na:1.6.0_13]
at java.lang.reflect.Method.invoke(Method.java:597) ~[na:1.6.0_13]
at org.codehaus.xfire.aegis.type.basic.BeanType.readProperty(BeanType.java:442) ~[xfire-all-1.2.6.jar:na]
at org.codehaus.xfire.aegis.type.basic.BeanType.writeObject(BeanType.java:377) ~[xfire-all-1.2.6.jar:na]
... 1015 common frames omitted