错误pointcut is null in InterceptorsChain

pointcut is null in InterceptorsChain2011-5-10 10:39:58 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet action threw exception
java.lang.NullPointerException
at com.jdon.aop.reflection.ProxyMethodInvocation.methodInvoke(ProxyMethodInvocation.java:105)
at com.jdon.aop.reflection.ProxyMethodInvocation.proceed(ProxyMethodInvocation.java:80)
at com.jdon.aop.interceptor.CacheInterceptor.invoke(CacheInterceptor.java:80)
at com.jdon.aop.reflection.ProxyMethodInvocation.proceed(ProxyMethodInvocation.java:88)
at com.jdon.aop.interceptor.SessionContextInterceptor.invoke(SessionContextInterceptor.java:84)
at com.jdon.aop.reflection.ProxyMethodInvocation.proceed(ProxyMethodInvocation.java:88)
at com.jdon.aop.interceptor.StatefulInterceptor.invoke(StatefulInterceptor.java:98)
at com.jdon.aop.reflection.ProxyMethodInvocation.proceed(ProxyMethodInvocation.java:88)
at com.jdon.aop.interceptor.PoolInterceptor.invoke(PoolInterceptor.java:95)
at com.jdon.aop.reflection.ProxyMethodInvocation.proceed(ProxyMethodInvocation.java:88)
at com.jdon.aop.AopClient.invoke(AopClient.java:110)
还有几个错误信息就不贴出来了。
请问怎样解决这个错误？