Using cockpit on tomcat (distribition: 7.0.0-alpha4) the following exception occurs, but I am able to reproduce it again

16.05.2013 15:02:47 org.jboss.resteasy.spi.ResteasyDeployment
INFO: Deploying javax.ws.rs.core.Application: class org.camunda.bpm.cockpit.impl.web.CockpitApplication
16.05.2013 15:02:47 org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher
INFO: Deploying javax.ws.rs.core.Application: class org.camunda.bpm.cockpit.impl.web.EngineRestApplication
16.05.2013 15:02:49 org.camunda.bpm.engine.impl.interceptor.CommandContext close
SCHWERWIEGEND: Error while closing command context
org.apache.ibatis.exceptions.PersistenceException:

1. 1. 1. Error querying database. Cause: java.lang.NullPointerException
      2. Cause: java.lang.NullPointerException
         at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:23)
         at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:104)
         at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:95)
         at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:59)
         at org.camunda.bpm.engine.impl.db.DbSqlSession.selectOne(DbSqlSession.java:301)
         at org.camunda.bpm.engine.impl.persistence.entity.ExecutionManager.findProcessInstanceCountByQueryCriteria(ExecutionManager.java:101)
         at org.camunda.bpm.engine.impl.ProcessInstanceQueryImpl.executeCount(ProcessInstanceQueryImpl.java:155)
         at org.camunda.bpm.engine.impl.AbstractQuery.execute(AbstractQuery.java:144)
         at org.camunda.bpm.engine.impl.interceptor.CommandExecutorImpl.execute(CommandExecutorImpl.java:24)
         at org.camunda.bpm.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:42)
         at org.camunda.bpm.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:32)
         at org.camunda.bpm.engine.impl.AbstractQuery.count(AbstractQuery.java:131)
         at org.camunda.bpm.engine.rest.impl.ProcessInstanceRestServiceImpl.queryProcessInstancesCount(ProcessInstanceRestServiceImpl.java:118)
         at org.camunda.bpm.engine.rest.impl.ProcessInstanceRestServiceImpl.getProcessInstancesCount(ProcessInstanceRestServiceImpl.java:105)
         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:597)
         at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:167)
         at org.jboss.resteasy.core.ResourceMethod.invokeOnTarget(ResourceMethod.java:257)
         at org.jboss.resteasy.core.ResourceMethod.invoke(ResourceMethod.java:222)
         at org.jboss.resteasy.core.ResourceMethod.invoke(ResourceMethod.java:211)
         at org.jboss.resteasy.core.SynchronousDispatcher.getResponse(SynchronousDispatcher.java:542)
         at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:524)
         at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:126)
         at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:208)
         at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:55)
         at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:50)
         at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
         at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
         at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
         at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
         at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
         at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
         at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:931)
         at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
         at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
         at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
         at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
         at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
         at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
         at java.lang.Thread.run(Thread.java:662)
         Caused by: java.lang.NullPointerException
         at org.apache.ibatis.reflection.property.PropertyTokenizer.<init>(PropertyTokenizer.java:27)
         at org.apache.ibatis.reflection.MetaObject.getValue(MetaObject.java:114)
         at org.apache.ibatis.builder.xml.dynamic.DynamicContext$ContextMap.get(DynamicContext.java:89)
         at org.apache.ibatis.builder.xml.dynamic.DynamicContext$ContextAccessor.getProperty(DynamicContext.java:107)
         at org.apache.ibatis.ognl.OgnlRuntime.getProperty(OgnlRuntime.java:1657)
         at org.apache.ibatis.ognl.ASTProperty.getValueBody(ASTProperty.java:92)
         at org.apache.ibatis.ognl.SimpleNode.evaluateGetValueBody(SimpleNode.java:170)
         at org.apache.ibatis.ognl.SimpleNode.getValue(SimpleNode.java:210)
         at org.apache.ibatis.ognl.ASTNotEq.getValueBody(ASTNotEq.java:49)
         at org.apache.ibatis.ognl.SimpleNode.evaluateGetValueBody(SimpleNode.java:170)
         at org.apache.ibatis.ognl.SimpleNode.getValue(SimpleNode.java:210)
         at org.apache.ibatis.ognl.Ognl.getValue(Ognl.java:333)
         at org.apache.ibatis.ognl.Ognl.getValue(Ognl.java:413)
         at org.apache.ibatis.ognl.Ognl.getValue(Ognl.java:395)
         at org.apache.ibatis.builder.xml.dynamic.OgnlCache.getValue(OgnlCache.java:42)
         at org.apache.ibatis.builder.xml.dynamic.ExpressionEvaluator.evaluateBoolean(ExpressionEvaluator.java:32)
         at org.apache.ibatis.builder.xml.dynamic.IfSqlNode.apply(IfSqlNode.java:30)
         at org.apache.ibatis.builder.xml.dynamic.MixedSqlNode.apply(MixedSqlNode.java:29)
         at org.apache.ibatis.builder.xml.dynamic.TrimSqlNode.apply(TrimSqlNode.java:42)
         at org.apache.ibatis.builder.xml.dynamic.MixedSqlNode.apply(MixedSqlNode.java:29)
         at org.apache.ibatis.builder.xml.dynamic.MixedSqlNode.apply(MixedSqlNode.java:29)
         at org.apache.ibatis.builder.xml.dynamic.DynamicSqlSource.getBoundSql(DynamicSqlSource.java:37)
         at org.apache.ibatis.mapping.MappedStatement.getBoundSql(MappedStatement.java:241)
         at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:79)
         at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:101)
         ... 43 more