I am using hibernate 3.2 with struts 1.2 framework I got this exception when i m trying to load the object

I am using this code to load the object

public Currentprofile findById(java.lang.String id) { log.debug("getting Currentprofile instance with id: " + id); try {

        Currentprofile instance = (Currentprofile) getSession().get(
                "com.hibermappings.Currentprofile", id);

        return instance;
    } catch (RuntimeException re) {
        log.error("get failed", re);
        throw re;
    }
}

my hbm file is this

    <one-to-one name="referenceDb" lazy="proxy" class="com.hibermappings.ReferenceDb" cascade="all" constrained="false" /> 
    <one-to-one name="registration" lazy="proxy" class="com.hibermappings.Registration" cascade="all" constrained="false" /> 
    <one-to-one name="jobseekerpackagedetails" lazy="proxy" class="com.hibermappings.Jobseekerpackagedetails" cascade="all" constrained="false" /> 

    <property name="keyWords" type="java.lang.String">
        <column name="keyWords" length="5000" />
    </property>
    <property name="totalExp" type="java.lang.String">
        <column name="totalExp" length="100" />
    </property>
    <property name="hqualification" type="java.lang.String">
        <column name="hQualification" length="100" />
    </property>
    <property name="preferedLocation" type="java.lang.String">
        <column name="preferedLocation" length="100" />
    </property>
    <property name="functionalArea" type="java.lang.String">
        <column name="functionalArea" length="1000" />
    </property>
    <property name="expSalary" type="java.lang.String">
        <column name="expSalary" length="100" />
    </property>
    <property name="designation" type="java.lang.String">
        <column name="designation" length="100" />
    </property>
    <property name="resumeTitle" type="java.lang.String">
        <column name="resumeTitle" length="500" />
    </property>
    <property name="profileDetails" type="java.lang.String">
        <column name="profileDetails" length="65535" />
    </property>
    <property name="requiredProfile" type="java.lang.String">
        <column name="requiredProfile" length="65535" />
    </property>
    <property name="activatedOn" type="java.util.Date">
        <column name="activatedOn" length="0" />
    </property>

    <set name="resumes" inverse="true" cascade="save-update">
        <key>
            <column name="jobseekerId" length="50" />
        </key>
        <one-to-many class="com.hibermappings.Resume" />
    </set>

</class>

the same code runs well when I m using in a simple java class within main method ..

full stack trace of exception is

java.lang.NullPointerException at org.hibernate.tuple.AbstractEntityTuplizer.createProxy(AbstractEntityTuplizer.java:372) at org.hibernate.persister.entity.AbstractEntityPersister.createProxy(AbstractEntityPersister.java:3121) at org.hibernate.event.def.DefaultLoadEventListener.createProxyIfNecessary(DefaultLoadEventListener.java:232) at org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:173) at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:87) at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:862) at org.hibernate.impl.SessionImpl.load(SessionImpl.java:781) at org.hibernate.impl.SessionImpl.load(SessionImpl.java:774) at com.DAOs.CurrentprofileDAO.getLoad(CurrentprofileDAO.java:71) at com.action.JobSekeerManage.viewProfile(JobSekeerManage.java:447) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:270) at org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:187) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) at javax.servlet.http.HttpServlet.service(HttpServlet.java:689) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:237) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157) at com.filter.HibernateFilter.doFilter(HibernateFilter.java:24) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:186) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:825) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:731) at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:526) at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684) at java.lang.Thread.run(Thread.java:595) Error::null