Exception in recent activity

2013-02-20 20:27:06 [DEBUG][http-8080-24    ][guroo][org.jtalks.jcommune.web.exception.PrettyLogExceptionResolver] - Resolving exception from handler [public org.springframework.web.servlet.ModelAndView org.jtalks.jcommune.web.controller.
BranchController.recentTopicsPage(java.lang.Integer)]: org.hibernate.NonUniqueResultException: query did not return a unique result: 2
2013-02-20 20:27:06 [WARN ][http-8080-24    ][guroo][                 org.jtalks.jcommune] - Handler execution resulted in exception
org.hibernate.NonUniqueResultException: query did not return a unique result: 2
        at org.hibernate.impl.AbstractQueryImpl.uniqueElement(AbstractQueryImpl.java:899)
        at org.hibernate.impl.AbstractQueryImpl.uniqueResult(AbstractQueryImpl.java:890)
        at org.jtalks.jcommune.model.dao.hibernate.LastReadPostHibernateDao.getLastReadPost(LastReadPostHibernateDao.java:50)
        at sun.reflect.GeneratedMethodAccessor286.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:319)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
        at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:90)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
        at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
        at $Proxy49.getLastReadPost(Unknown Source)
        at org.jtalks.jcommune.service.transactional.TransactionalLastReadPostService.fillLastReadPostForTopics(TransactionalLastReadPostService.java:58)
        at sun.reflect.GeneratedMethodAccessor307.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:319)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
        at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)