Problema em Obter DataSource/Connection from GlassFish Pool

Bom dia pessoal

Estou com problema em relação a busca do objeto DataSource/Connection do pool do glassfish.
Estou debugando no Netbeans a aplicação ou somente utilizando o glassfish embutido, e quando altero alguma classe e é implantado novamente, começa da erro ao obter o connection. Se eu para o GlassFish e tentar novamente volta a funcionar normalmente. Alguém pode me ajudar?

Detalhes: Não estou utilizando framework de persistência. No glassfish configurei tanto o pool de jdbc quando o jdbc resource.

Abaixo o erro:

[code]GRAVE: java.sql.SQLException: Error in allocating a connection. Cause: null
at com.sun.gjc.spi.base.DataSource.getConnection(DataSource.java:120)
at br.com.acifranca.conexao.Conexao.getConnection(Conexao.java:43)
at br.com.acifranca.dao.BaseDAO.getConnection(BaseDAO.java:26)
at br.com.acifranca.dao.BaseDAO.createStatemant(BaseDAO.java:35)
at br.com.acifranca.dao.usuario.UsuarioDAOImpl.login(UsuarioDAOImpl.java:291)
at br.com.acifranca.web.beans.LoginBean.acessar(LoginBean.java:44)
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 javax.el.BeanELResolver.invokeMethod(BeanELResolver.java:737)
at javax.el.BeanELResolver.invoke(BeanELResolver.java:467)
at javax.el.CompositeELResolver.invoke(CompositeELResolver.java:254)
at com.sun.el.parser.AstValue.invoke(AstValue.java:228)
at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:297)
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
at javax.faces.event.MethodExpressionActionListener.processAction(MethodExpressionActionListener.java:148)
at javax.faces.event.ActionEvent.processListener(ActionEvent.java:88)
at javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:769)
at javax.faces.component.UICommand.broadcast(UICommand.java:300)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:662)
Caused by: javax.resource.spi.ResourceAllocationException: Error in allocating a connection. Cause: null
at com.sun.enterprise.connectors.ConnectionManagerImpl.internalGetConnection(ConnectionManagerImpl.java:307)
at com.sun.enterprise.connectors.ConnectionManagerImpl.allocateConnection(ConnectionManagerImpl.java:190)
at com.sun.enterprise.connectors.ConnectionManagerImpl.allocateConnection(ConnectionManagerImpl.java:165)
at com.sun.enterprise.connectors.ConnectionManagerImpl.allocateConnection(ConnectionManagerImpl.java:160)
at com.sun.gjc.spi.base.DataSource.getConnection(DataSource.java:113)
… 50 more
Caused by: com.sun.appserv.connectors.internal.api.PoolingException
at com.sun.enterprise.resource.pool.datastructure.RWLockDataStructure.addResource(RWLockDataStructure.java:103)
at com.sun.enterprise.resource.pool.ConnectionPool.addResource(ConnectionPool.java:282)
at com.sun.enterprise.resource.pool.ConnectionPool.createResourceAndAddToPool(ConnectionPool.java:1501)
at com.sun.enterprise.resource.pool.ConnectionPool.createResources(ConnectionPool.java:944)
at com.sun.enterprise.resource.pool.ConnectionPool.resizePoolAndGetNewResource(ConnectionPool.java:792)
at com.sun.enterprise.resource.pool.ConnectionPool.getResourceFromPool(ConnectionPool.java:760)
at com.sun.enterprise.resource.pool.ConnectionPool.getUnenlistedResource(ConnectionPool.java:632)
at com.sun.enterprise.resource.pool.ConnectionPool.internalGetResource(ConnectionPool.java:526)
at com.sun.enterprise.resource.pool.ConnectionPool.getResource(ConnectionPool.java:381)
at com.sun.enterprise.resource.pool.PoolManagerImpl.getResourceFromPool(PoolManagerImpl.java:242)
at com.sun.enterprise.resource.pool.PoolManagerImpl.getResource(PoolManagerImpl.java:167)
at com.sun.enterprise.connectors.ConnectionManagerImpl.getResource(ConnectionManagerImpl.java:338)
at com.sun.enterprise.connectors.ConnectionManagerImpl.internalGetConnection(ConnectionManagerImpl.java:301)
… 54 more
Caused by: com.sun.appserv.connectors.internal.api.PoolingException
at com.sun.enterprise.resource.pool.ConnectionPool.createSingleResource(ConnectionPool.java:924)
at com.sun.enterprise.resource.pool.ConnectionPool.createResource(ConnectionPool.java:1185)
at com.sun.enterprise.resource.pool.datastructure.RWLockDataStructure.addResource(RWLockDataStructure.java:98)
… 66 more
Caused by: java.lang.NullPointerException
at com.microsoft.sqlserver.jdbc.FailoverMapSingleton.getFailoverInfo(FailOverMapSingleton.java:37)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:685)
at com.microsoft.sqlserver.jdbc.SQLServerDataSource.getConnectionInternal(SQLServerDataSource.java:593)
at com.microsoft.sqlserver.jdbc.SQLServerDataSource.getConnection(SQLServerDataSource.java:57)
at com.sun.gjc.spi.DSManagedConnectionFactory.createManagedConnection(DSManagedConnectionFactory.java:113)
at com.sun.enterprise.resource.allocator.LocalTxConnectorAllocator.createResource(LocalTxConnectorAllocator.java:87)
at com.sun.enterprise.resource.pool.ConnectionPool.createSingleResource(ConnectionPool.java:907)
… 68 more

[/code]

desde já agradeço